Preheat oven 350 degrees

Heat 1 T oil in large skillet/medium heat. Add peppers, onions, 1/4 t salt and 1/4 t pepper; and cook 10-20 min, stirring occasionally, until deep golden brown and caramelized. Transfer to a large bowl.

With the skillet back to heat, add remaining 1/2 T oil and spinach and cook 2-3 min, tossing often until completely wilted and liquid is evaporated. Transfer to same large bowl with the peppers and onions. Set aside to cool.

Add eggs, milk, 1/2 c of cheese, thyme and remaining salt and pepper to large bowl; stir to combine.

Transfer to pie crust, top with remaining 1/4 c cheese. Bake 45 min until deep golden brown and cooked through. Set aside to cool. Cut and serve while warm.