Arrange top rack in oven to 7 inches from the broiler element. Preheat broiler to high.
Heat a large broiler-safe skillet over medium heat. Add oil to pan and reduce heat to low. Stir in garlic; gently cook garlic 3-4 minutes or until it's soft and translucent, stirring frequently and removing the pan from the heat periodically, if necessary to prevent browning or burning the garlic. Turn heat off and stir in tomatoes. Sprinkle with salt and pepper flakes.
Place pan in oven on top rack; broil 10 minutes or until tomatoes blister lightly and begin to burst, stirring after 6 minutes. Remove pan from oven; stir tomato mixture well to combine, sprinkle with basil.
I love the vibrant color of the rainbow blend of cherry tomatoes, but this recipe will taste just as delicious with just red tomatoes. You'll need to carefully cook the garlic very slowly over low heat, stirring frequently to make sure you don't burn or scorch. If it does burn, you'll have to start all over with fresh oil and garlic.