The Keto Baking Mechanic™ — Recipes

99 Second Keto “Rye” Sourdough

Where We Create, Tweak and Enhance
Keto and Low Carb Breads and Baked Goods

🏓 Real Sourdough Tang, Real Rye Character, 99 Seconds

If you have been searching for a true keto bread that actually tastes like bread, this recipe changes the game. Unlike many low-carb breads that rely on artificial tang or flavour additives, this version uses authentic sourdough discard to create real depth of flavour, structure, and traditional rye-style character.

This 99 Second Keto “Rye” Sourdough is designed for speed, simplicity, and authentic sourdough personality. It is hearty, fibre-rich, toaster-friendly, and balanced enough for butter, peanut butter, sandwiches, or serving alongside soups and salads.

Unlike many microwave keto breads that taste soft or eggy, this version develops a more traditional rye-style character once cooled and toasted. The combination of flax, psyllium, caraway, and authentic sourdough discard creates a hearty texture designed for real bread lovers.

This is not faux sourdough flavour — faux dough — created with vinegar or flavouring agents. The tang comes from authentic sourdough fermentation.

https://sinlesssourdough.com/shop/

The Difference

What Makes This Recipe Different

Many keto bread recipes focus only on lowering carbohydrates. This recipe focuses on:

The Discard Contributes

Instead of creating a soft cake-like microwave bread, this system creates a dense, hearty loaf designed for slicing and toasting. The flax and psyllium structure also help support moisture retention while keeping net carbohydrates low.

The Science

Why It Works

Low-carb baking behaves very differently from traditional wheat baking. Without large amounts of starch, keto breads often struggle with:

This recipe works by combining finely ground flax seeds and psyllium husks to create a hydrated fibre network that traps steam during microwave cooking.

The sourdough discard contributes flavour and moisture while the baking powder creates rapid lift. Together, these elements create a moist, sliceable keto bread with rye-style character.

What to Expect

Taste & Texture

This keto bread has:

The flavour improves significantly after cooling and toasting.

The caraway seeds help create a familiar rye bread flavour profile without the high carbohydrates found in traditional rye flour.

Philosophy

About Measurements & Precision in Keto Sourdough

Traditional baking often teaches that cooking is art, but baking is science — meaning it must be precise. That’s why many bakers prefer weighing ingredients in grams instead of using cups.

Keto sourdough baking does not follow that traditional model. Sinless Sourdough is a living fermentation system. Your starter changes daily depending on hydration, environment, temperature, feeding cycle, and ingredient brand. Because of this, no two bakes are ever identical.

Gram measurements listed in Sinless recipes are approximate reference points based on commonly available brands. However, ingredient density varies depending on brand, grind size, how tightly ingredients are packed, humidity, and storage conditions. This is especially true for psyllium husks, active starter, flax meal, and fibre ingredients.

Your starter’s weight will vary from day to day depending on how aerated or dense it is when measured.

Learning to Read Dough

The goal is not to hit an exact number on a scale. The goal is to build proper dough structure. Watch your dough:

Cups or grams — either works. Hydration awareness is what creates success. Sinless Sourdough is not about rigid precision. It is about learning to read your dough.

What You’ll Need

Ingredient Breakdown

• Living Biome Boss Sourdough Discard: Adds authentic fermented flavour, acidity, moisture, and sourdough aroma. Available at sinlesssourdough.com/shop/
• Golden Flax Seeds: Provide structure, fibre, healthy fats, and help create a more bread-like texture once ground
• Whole Psyllium Husks: Help bind the dough while supporting elasticity and sliceability
• Egg: Provides lift, protein, and moisture balance
• Double-Acting Baking Powder: Creates rapid expansion during microwave cooking
• Caraway Seeds: Give the bread its classic rye-style flavour profile

What You’ll Need

Equipment

• Microwave-safe glass dish
• Small mixing bowl
• Spoon or spatula
• Coffee grinder
• Wire cooling rack

Ingredients

• 1 egg
• 3 tablespoons living Biome Boss sourdough discard
• 3 tablespoons golden flax seeds
• 1 tablespoon whole psyllium husks
• ½ tablespoon double-acting baking powder
• ¼ teaspoon salt (optional)
• 1 teaspoon caraway seeds

Let’s Bake

Step-by-Step Instructions

Step 1 — Prepare the Wet Ingredients

Add the egg and living Biome Boss sourdough discard to a bowl. Mix until fully combined.

Step 2 — Grind the Fibre Ingredients

Using a coffee grinder, grind together the golden flax seeds and whole psyllium husks until the mixture resembles a coarse meal. This step helps improve texture and reduce grittiness.

Add the ground mixture to the bowl.

Step 3 — Add Remaining Ingredients

Add the double-acting baking powder, salt (optional), and caraway seeds. Mix thoroughly.

The dough will begin thickening quickly as the fibres absorb moisture.

Step 4 — Transfer to Baking Dish

Spray a microwave-safe glass dish with avocado oil spray or olive oil spray. Transfer the thickened dough to the dish and smooth evenly to the edges. Place the dish near the outer edge of the microwave plate for more even cooking.

Cover with a silicone cover, paper towel, or microwave-safe lid.

Step 5 — Microwave

Microwave for 99 seconds. Microwave performance varies slightly between units, so small timing adjustments may be necessary. The bread should feel set on top when finished.

Step 6 — Cool & Slice

Remove from microwave and allow the bread to cool slightly. Transfer to a wire rack and cool before slicing horizontally. Cooling helps stabilize the structure and improves texture.

No Microwave?

Toaster Oven, Convection Oven Or Air Fryer

You can also bake this keto bread in a toaster oven, convection oven, or air fryer instead of using the microwave. Because all units cook differently, watch the bread closely during baking and adjust timing as needed.

Approximate Baking Times at 350°F (177°C)

The bread should feel set on top and lightly firm to the touch when finished. These dry-heat methods create a slightly firmer exterior and a texture more similar to traditional toasted bread compared to the softer microwave version.

Allow the bread to cool before slicing for the best structure and texture.

Fermentation

Fermentation Context

Although this is a rapid bread, the inclusion of authentic sourdough discard still contributes fermentation compounds developed during the starter’s feeding cycle.

The discard introduces:

This creates a more authentic bread experience compared to recipes that attempt to imitate sourdough flavour using vinegar or flavour additives alone.

Digestibility Positioning

Authentic sourdough fermentation has traditionally been valued for flavour, texture, and baking performance. Many bakers also appreciate sourdough because fermentation may help improve dough behaviour and contribute to a more developed bread structure.

This recipe is designed to align with authentic sourdough principles while remaining keto low-carb friendly.

Troubleshooting

Common Mistakes

Make It Your Own

Variations

Strict Keto Version

Use the recipe exactly as written.

Additional Rye-Style Flavour

Optionally add a pinch of onion powder or a pinch of dill.

Toasting Version

Toast slices lightly for improved structure and rye-style character.

By the Numbers

Nutrition

Whole Loaf

One Slice (Half Loaf)

Net carbohydrates are calculated as total carbohydrates minus dietary fibre.

Keeping It Fresh

Storage

Store refrigerated in an airtight container for up to 4 days.

For Best Texture

Setting Expectations

Practice Batch Philosophy

Keto sourdough baking is a skill-building process. Your first loaf teaches:

Do not judge the system from a single batch. Every bake teaches you how your ingredients behave in your environment. That is how confident keto sourdough bakers are built.