Mix meat with onion and cook in 1tablespoon melted butter over low heat for about 20 minutes.
Add enough water to barely cover, put a heavy lid on the pot, and cook until done.
In a separate casserole melt 1tablespoon butter and add peas, sugar, salt and parsley. Start cooking over low heat. After about 5 minutes add a little water. Do not cover the pot, because when peas are cooked there should be no liquid left in the pot.
Add flour, stir, and cook for 2 more minutes.
Mix peas with meat and its juice and simmer over very low heat for 1 or 2 more minutes.