Soften yeast in warm water; let stand 10 minutes.

Mix cottage cheese, sugar, butter, 1 teaspoon salt, and baking soda together in a large mixing bowl. Add dill seed, dried onion, egg, and yeast mixture; mix well. Gradually add flour, about 1/4 cup at a time, stirring well after each addition. If dough seems too sticky, add another 1 to 2 tablespoons flour.

Cover the bowl with a clean cotton kitchen towel and place in a warm place until doubled in volume, about 1 hour.

Preheat the oven to 350 degrees F (175 degrees C). Generously butter a 1 1/2- to 2-quart baking dish.

Gently stir dough to release bubbles. Transfer to the prepared baking dish.

Bake in the preheated oven until golden brown, about 35 minutes. Remove from the oven; brush the top with melted butter and sprinkle on a pinch of salt. Leave in the pan for 5 minutes before transferring to a wire rack to cool completely.