In oil, saute chopped onion 2 minutes. Add squash cook 2 mintues. Add chiles, tomatoes, pepper flakes, and 1 c water, salt & pepper. Boil, cover reduce heat and simmer 15 minutes. In separate pot, bring stock to boil. Add bulgur. Cover pan, reduce heat, cook 20 minutes. Meanwhile heat 2nd olive oil, saute sliced onions until golden. Remove bulgur from heat, set in warm place 20 minutes. Layer on plate: bulgur, squash sliced onions, then top with yogurt which has been beaten with the crushed garlic.