Slice each chicken breast horizontally into two thin fillets or pound them to an even thickness, then divide each breast in half to make four portions. Sprinkle both sides of each piece with salt and pepper.

Warm a large skillet over medium heat. When the skillet is hot, add 1 tablespoon of olive oil, coating the surface. Lay the chicken pieces in the skillet, cooking until both sides are golden and cooked through, approximately 7-10 minutes in total. Transfer the chicken to a plate.

Lower the heat to medium-low and add the remaining tablespoon of olive oil to the skillet. Stir in the minced garlic and halved grape tomatoes, sautéing for about 5 minutes until the tomatoes start to soften and break down.

Pour in the heavy cream and pesto, stirring to combine with the tomatoes. Let the sauce come to a gentle simmer, then taste and season with additional salt or pepper if desired.

Return the chicken to the skillet, turning to coat each piece in the creamy pesto sauce. Simmer for a few minutes more to warm the chicken through. Serve hot.