Melt butter in pot.
Cut onion in half and place, cut side down, into the butter. Let it get some colour.
Add crushed, but uncut, clove into the butter. Do not let it burn.
Crush tomatoes with hands, remove hard bits, put in pot.
Let simmer uncovered for a minimum of 45 minutes.
Remove onion halves and garlic before serving.
This is based off of Marcella Hazan’s recipe.