Sourdough Croque Madame with Tomato

Method

1. In a bowl, mix 1 cup flour, 1/2 tsp salt, and 1/4 tsp yeast. Add 3/4 cup water and stir until a dough forms. Cover and let ferment for 12–18 hours at room temperature.
2. Preheat oven to 375°F (190°C).
3. Butter both sides of sourdough slices.
4. Layer ham and Gruyère on one slice, top with another slice.
5. Bake for 10–12 minutes until golden and crisp.
6. Top with sliced tomato and basil leaves.
7. Cook eggs in a pan until the whites are set.