Add one tbsp of olive oil in a skillet, add spinach, quarter cherry tomatoes, and chopped garlic. Cook it until spinach is soft
Make pockets in chicken breasts. Salt, pepper, you can add Mediterranean dry herbs ( basil, oregano). I had three chicken breasts so I first stuffed each with one tbsp of cheese and then cooked greens. Close cuts with wooden toothpicks.
Brown chicken in the skillet on both side (don't cook it). then transfer into a deep tray with the remaining tbsp of olive oil
Distribute marinara sauce evenly on top of the chicken. Cover with foil.
Preheat oven to 375F. Cook till it done.
As a final step sprinkle remaining cheese on top of the chicken, send it back to oven for a few min for cheese to melt. Enjoy!