The Philosophy of the “Scrap”

In the busy patisseries of Paris, nothing ever went to waste. We treated every “scrap”—whether it was a trim of puff pastry or a bowl of sourdough discard—as an opportunity for more flavor. The first time I made these overnight sourdough discard waffles for my colleagues at Pierre Hermé, they couldn’t believe they weren’t eating a complex, multi-day yeasted brioche. The secret to masterfully baking with sourdough discard is simply time and the right visual cues.

I know what you’re thinking: waffles are supposed to be a quick Saturday morning affair. But if you’re looking for that legendary shatteringly crisp exterior and a tender, custard-like crumb found in the best waffles, you have to respect the science of the overnight ferment. This isn’t just about convenience; it’s about unlocking a complex, nutty profile that no “instant” mix can replicate in these artisan breakfast recipes.

Sourdough Waffle Science: Why the Overnight Rest Matters

Here’s why this matters: while you sleep, the enzymes in your sourdough starter are working hard to hydrate the flour’s starches and break down phytic acid. This process, which we call enzymatic activity, creates a “short” texture that is much easier for your body to digest and far more flavorful.

By the time you wake up, your “sponge” has transformed into a fermented flavor-concentrate. When we introduce the baking soda in the morning, it reacts with the accumulated lactic acid to create a massive carbon dioxide release. This is where the magic happens—instant aeration within the fermented waffle batter that results in a waffle so light it almost feels hollow, yet remains incredibly sturdy.

The Professional “Soufflé” Technique

To take these from “good” to “artisan,” we borrow a technique from French soufflés. Instead of just tossing in whole eggs, we separate them. This is the key to achieving truly crispy sourdough waffles.

The most critical moment is the Sacrificial Fold. You’ll notice the overnight batter is quite dense. If you try to fold delicate egg whites directly into that heavy mass, you’ll deflate them instantly. Instead, take about a quarter of your whipped whites and stir them in quite vigorously. You’re “sacrificing” those bubbles to lighten the base. Once the batter has reached a more supple, “lava-like” flow, you can gently fold in the remaining whites.

Mia’s Tips for Success

• Temperature is everything: Make sure your discard is at room temperature. If it’s too cold, your beautiful European butter will seize into hard little pebbles, and you’ll lose that even, fatty distribution that creates the “shatter” effect.
• The European Butter Advantage: I always use butter with at least 82% butterfat. Lower-quality butters have a higher water content, which creates steam and leads to a tougher, breadier waffle rather than a crisp one.
• The Wire Rack Rule: Never, ever stack your waffles on a plate. The steam from the bottom waffle will rise and soften the one above it. Always place them on a wire cooling rack in a low oven (200°F/95°C) until you’re ready to serve. If you have leftovers, they make excellent freezer waffles.

Don’t be intimidated by the idea of “planning ahead.” This recipe is actually more forgiving than a standard quick-mix because the gluten has had all night to relax. You’ve got this, I promise. Practice makes better—not perfect, better—and your first bite of these golden-brown beauties will be all the proof you need.