stirring frequently, don’t burn them (at least 10 minutes). add the garlic into the pan with the onions and cook for several more minutes. grate the tomatoes over the pan, if you are just using a smaller amount of tomatoes.
otherwise grate all those tomatoes in a bowl separately and then put them in with the onions. grating the tomatoes, with a cheese grater over the pan or bowl, is the quick way to peel tomatoes, because the skin stays in your hand and the pulp goes in the pan/bowl. if you hate using a cheese grater, and some folks do, you can also steam the tomatoes, let them cool and 