Grilled Potato Spinach Quesadillas

Name: Grilled Potato Spinach Quesadillas
Prep time: 20 min
Cook time: 25 min
Total time: 45 min
Cuisine: American
Ingredients: 1 ½ pounds potatoes (peeled; preferably a white or yellow potato variety, such as russet or Yukon gold.); ¼ cup milk of choice (I prefer unsweetened almond milk); 2 Tbsp butter (use Earth Balance or substitute with olive oil to keep vegan); 2 Tbsp mascarpone; 1 tsp sea salt; ½ tsp garlic powder; ½ tsp onion salt; 2-3 cups fresh spinach (or 8-12 oz frozen); 1-2 cups cheddar; Tortillas; olive oil or canola oil (for frying)