American Bakery
Fudgy Double-Chocolate Sourdough Discard Brownies
Dense, truffle-fudgy dark chocolate brownies with a glossy, tissue-thin crinkle top: whipping aquafaba with cane sugar dissolves sucrose crystals for the signature papery sheen, while 120 grams of sourdough discard supplies pre-digested wheat structure and subtle lactic tang that intensifies dark cocoa.
The good part
Fermentation Science & Baker’s Notes
Because 120g of sourdough discard already contains 60g of pre-hydrated, enzymatically relaxed flour, these brownies require only 1/2 cup of dry flour—producing an extraordinarily dense, fudge-truffle texture with zero dryness. For deeper fermentation diagnostics, Desired Dough Temperature math, and starter ratios, consult our The Zero-Waste Sourdough Discard Playbook and the master Vegan Sourdough & Wild Fermentation Pillar Hub.
Storage, Freezing & Refreshing
Store crusty artisan sourdough loaves cut-side down on a wooden board or inside a linen bread bag at room temperature for up to 3 days (avoid sealed plastic bags, which trap moisture and soften the blistered crust). For longer storage, slice the cooled loaf completely, place parchment squares between slices, and freeze in an airtight freezer bag for up to 3 months; toast straight from frozen or refresh whole loaves in a 375°F oven for 8 minutes.
Nutrition, Digestibility & Swaps
Even fudgier on Day 2 after chilling overnight in an airtight container. Want to adapt another family bakery recipe to 100% plant-based sourdough? Open our interactive Vegan Baking Converter.
Gather
Ingredients
- 150g (5.3 oz) 70%–72% dark vegan chocolate, chopped (plus 85g / 1/2 cup dark chocolate chunks for folding in)
- 115g (1/2 cup / 1 stick) vegan block butter
- 1 tsp instant espresso powder
- 75g (5 tbsp) aquafaba (chickpea liquid, at room temperature)
- 150g (3/4 cup) organic cane sugar + 75g (1/3 cup packed) dark brown sugar
- 120g (1/2 cup) unfed 100%-hydration sourdough discard (room temperature)
- 1 1/2 tsp pure vanilla extract
- 65g (1/2 cup + 1 tbsp) unbleached all-purpose flour (minimal extra flour needed since discard supplies 60g fermented flour!)
- 45g (1/2 cup) Dutch-process cocoa powder + 1/2 tsp fine sea salt + flaky sea salt for top
Make
Method
- 01Melt Dark Chocolate, Butter & Espresso: Line an 8x8-inch metal baking pan with a parchment sling and preheat oven to 350°F (175°C). Melt the 150g chopped dark chocolate, 115g vegan butter, and 1 tsp espresso powder together over a gently simmering water bath until glossy; remove from heat.
- 02Whip Aquafaba & Sugars for Crinkle Top: In a bowl using a hand mixer or whisk, beat the 75g aquafaba, cane sugar, and brown sugar for 2 to 3 minutes until pale, thick, and foamy (dissolving the sugar in aquafaba creates the papery meringue crust on top).
- 03Whisk in Melted Chocolate & Sourdough Discard: Whisk the warm melted chocolate-butter mixture, 120g sourdough discard, and vanilla into the whipped aquafaba until satin-smooth.
- 04Fold Cocoa, Flour & Chocolate Chunks: Sift the 65g flour, Dutch cocoa powder, and sea salt over the bowl; fold gently with a spatula just until combined, then fold in the 85g dark chocolate chunks.
- 05Bake & Chill for Clean Truffle Slices: Spread into the prepared 8x8-inch pan, sprinkle with flaky sea salt, and bake at 350°F for 26 to 30 minutes until the top is shiny and crinkled and a tester comes out with moist fudgy crumbs (do not overbake). Cool completely in the pan before slicing into 16 squares.
Keep cooking
Swaps, storage, and useful next steps.
Even fudgier on Day 2 after chilling overnight in an airtight container.