Prep the bread: Slice bread into thick slices (about 3/4 to 1 inch). If it’s very fresh, leave slices out for 10–15 minutes to dry slightly. Slightly stale bread absorbs custard better and won’t get soggy.
Make the custard: In a mixing bowl, whisk 3 large eggs, 1/2 cup plain Greek yogurt, and 1/2 cup milk until smooth.
Add 1 teaspoon vanilla, 1/2 to 1 teaspoon cinnamon, a pinch of salt, and 1–2 teaspoons sugar or maple syrup. Whisk until the mixture is silky and no yogurt lumps remain.
Heat the pan: Place a large nonstick skillet or griddle over medium heat. Add 1 tablespoon butter.
When it foams and smells nutty, you’re ready to cook.
Soak the bread: Pour the custard into a shallow dish. Dip each slice for about 15–20 seconds per side. The bread should be evenly coated but not falling apart.
Shake off excess.
Cook the first batch: Lay slices in the hot pan without crowding. Cook 2–3 minutes per side, until golden brown with crisp edges. Adjust heat if they brown too quickly.
Finish and repeat: Add a little more butter between batches as needed.
Keep cooked slices warm on a baking sheet in a 200°F (95°C) oven while you finish the rest.
Serve: Top with a dollop of Greek yogurt, maple syrup, and berries. Add a dusting of powdered sugar if you like.