Whisk the custard: In a shallow bowl, whisk eggs, heavy cream, sweetener, vanilla, cinnamon, nutmeg, and salt until smooth and slightly frothy.
Prep the bread: If your keto bread is very soft, let slices sit out for 5–10 minutes to dry slightly. This helps them soak without falling apart.
Heat the pan: Place a large nonstick skillet over medium heat.
Add butter or coconut oil and let it melt and coat the pan evenly.
Soak the slices: Dip one slice at a time into the custard. Let it soak for about 10–15 seconds per side. Aim for saturated but not soggy.
Cook to golden: Lay soaked slices in the hot pan.
Cook 2–3 minutes per side, until deeply golden with crisp edges. Adjust the heat so the toast browns without burning.
Finish the batch: Repeat with remaining slices, adding a touch more butter or oil if the pan looks dry.
Serve warm: Plate immediately with your favorite keto-friendly toppings. A pat of butter and a drizzle of sugar-free syrup keep it classic.