A garden tomato based sauce with tomatoes, onions & peppers.
Heat olive oil in a medium saucepan, add onion and peppers and cook until slightly softened. Add garlic, cumin and cayenne and cook for just a minute longer. Add tomatoes and juice and simmer until vegetables are cooked through and softened and sauce is thickened, about 15 minutes. When a spoon is run through the sauce it should not immediately fill in.
Add the sugar, salt to taste and vinegar and cook for a minute or two longer to blend the flavors.
Feel free to increase/decrease the amounts of sugar, salt, Jalapeno or Serrano, cayenne, vinegar, etc. to suit your taste.
Notes: to prepare the jalapeno or serrano, char over a gas burner or put on a piece of foil on a sheet tray and broil, turning as needed until charred. When finished, put in a small bowl and cover for several minutes. Remove the charred coating.
Tomatoes: In the summer, I often use fresh tomatoes, about 2 pounds, peeled & seeded, with their juice.