1Melt butter in a skillet over medium heat until it foams. Stir in garlic; cook until edges just start to turn golden, about 2 minutes.
2Stir balsamic vinegar into skillet, bring to a simmer and cook over medium heat until vinegar is reduced by 2/3 to create a thick sauce, 1 to 2 minutes.
3Stir in chile peppers and reduce heat to low.
4Whisk in tomato paste, salt and black pepper. Remove skillet from the heat.
5Stir in butter; whisk constantly until the butter melts and is completely incorporated into the sauce.