Cheese Galette

Whisk an egg with kefir. Add flour, salt, and baking powder. Mix until you have a soft dough that doesn't stick to your hands. Wrap it in plastic wrap and refrigerate for 30 minutes.

Divide the dough in half. Roll each piece out on a lightly floured surface. In the center, pile your mixture of grated cheese, sliced tomatoes, and herbs. Carefully fold up the edges to form a galette. Brush the top with egg yolk.