Cover buckwheat groats wit 2.5 cups of boiling water, add salt, cover and cook on a low heat for 25 minutes. Peel garlic and slightly crush the cloves. Put the cloves in a small saucepan, cover with oil and simmer. Brown garlic, then put on a plate with a slotted spoon. Peel onions and slice into semi-circles. Remove the rigid ends of oyster stipes. Cut big caps into pieces, and leave small ones intact. Heat garlic oil in a frying pan and put onions. Fry under a high heat for 5 minutes, stirring frequently. Add oyster mushrooms and fry for another 5 minutes. Salt, sprinkle with paprika, stir and remove from fire. Mix mushrooms with onions, and garlic with buckwheat porridge and serve.