Start by horizontally slicing the chicken breasts into thin cutlets, which will help them cook quickly and evenly.

In a shallow dish, combine plain flour, garlic powder, salt, and black pepper. Mix well and coat each chicken cutlet.

Heat a large skillet over medium heat and add olive oil and butter. Once hot, add the chicken cutlets and cook for about 3-4 minutes per side until golden brown.

Lower the heat slightly and add diced shallots to the skillet, sautéing for about 3-4 minutes until soft and golden.

Pour in chicken stock, heavy cream, and freshly grated Parmesan, stirring well. Let it simmer for about 5 minutes until thickened.

Add halved cherry tomatoes to the sauce and simmer for another 2-3 minutes.

Stir in the pesto and cook for 1-2 minutes, then add the chicken back into the skillet, coating it in the sauce.

Let everything simmer together for another minute before serving.