Pour water over the rice and leave for 20-30 minutes, then rinse well until the water becomes clear. Wash and wipe the tomatoes and bell peppers. Remove the stem, membranes and seeds from the bell pepper, and peel the tomatoes. Peel and rinse the garlic. Wash the chicken egg well. Grate Parmesan on a coarse grater. For baking, prepare a baking dish greased with vegetable oil. To prepare the sauce, take out the blender.
Prepare the minced meat. In a deep bowl, mix minced meat with rice, beat in a chicken egg, add salt and ground black pepper. Knead the minced meat well for 10-15 minutes. Form the minced meat into equal small balls.
Make the sauce. Cut the peeled tomatoes into 4 parts, cut the bell pepper into large slices, pass the garlic cloves through a press. Place tomatoes and peppers in a blender bowl and blend until pureed. Add Greek yogurt, salt, black pepper and garlic to the vegetables. Blend the sauce in a blender again until smooth.
Bake the hedgehogs. Preheat the oven to 180 degrees. Place the minced meat balls in a greased form and pour in the sauce. Place thyme sprigs on top. Place the form with hedgehogs in the oven for 20 minutes. Then remove the hedgehogs, sprinkle them with grated Parmesan and return to the oven for another 15 minutes.
Serve the finished hedgehogs with thyme along with a side dish of mashed potatoes, first topped with a sauce of yogurt and vegetables.