Preheat the oven to 375F.

In a large pan, heat up 1 ½ tablespoon of oil over medium-high heat. Season the chicken tenders with salt and pepper, and add to the pan once the oil is hot. Cook for 7-10 minutes, until the outside develops a golden brown crust and the inside is completely white and cooked through.

Remove the chicken from the pan, and add the rest of the oil, along with the garlic. Add in the mushrooms, and saute them for a couple of minutes. Add in the chopped spinach, and cook the vegetables until the spinach has wilted, and the mushrooms are browned. Transfer the vegetables to a large bowl to cool off.

Grab the cooked chicken tenders, cut them into bite-sized pieces, and add them to the bowl with the vegetables. Using a spatula or wooden spoon, mix the cheeses and pesto into the same bowl. Add in the eggs, mixing after each, then add the milk. Pour the mixture into the frozen pie crust, and top with more pesto and cheese if desired.

Place the pie on a baking sheet, and bake for 40-50 minutes, until the crust is golden brown and the egg is completely firm and cooked through.

Bake the first 20 minutes uncovered, then place a piece of foil over the pie for the last half of the cooking time. Let cool before cutting and enjoying!