Fluffy pan-fried  flat cakes with filling

Ingredients

• 500 ml yogurt
• 1 tsp baking soda
• 1 egg
• 2 tbsp oil
• 500-550 g flour
• 50 g butter
• salt to taste
• more oil for greasing and frying
• more butter for greasing cakes when ready
• white cheese with herbs
• minced meat fried with onion, egg
• mushrooms fried with onion
• canned fish with hard boiled egg
• stewed cabbage
• mashed potato with herbs
• chopped green onion with hard boiled egg
• dried fruit soaked and chopped
• thick jam
• nutella