Cut grape tomatoes in half, place in bowl with Balsamic Vinegar, 2 TBSP Olive Oil, chopped basil and 1 clove of finely chopped garlic. Let marinate for at least 1 hour.
Boil water, and cook penne pasta per directions, until al dente
In saute pan, place 2 TBSP olive oil and saute the other finely chopped garlic clove on medium heat for approximately 2 minutes. Add the tomato mixture to saute pan and cook until mixture is bubbling and tomatoes begin to soften, approx 3 minutes. Add extra balsamic vinegar and/or pasta water if needed.
Cube Mozzarella, and toss tomato mixture with pasta and cheese. Let sit for 2-3 minutes to allow cheese to melt. Salt and pepper to taste.