Prep Dough: Preheat oven to 400 degrees F (204 C). If working with frozen phyllo, allow 30 minutes or so to bring to room temperature. Once thawed, lightly grease a pie pan. Brush one side of each slice of phyllo with butter, then lay butter side-up in the pan. Lay sheets so that they cover the bottom and sides of the pan, with a little extra phyllo hanging over (they'll overlap a bit, this is good!)
Whipped Feta: To a food processor add feta, ricotta, garlic, salt, and pepper. Blitz until smooth and creamy.
Assemble: Peel then thinly slice beets, potatoes, and apple. Spoon the whipped feta onto the phyllo, then lay in the veggies (either arranged nicely or all thrown in!) Gently crumble phyllo dough that is left on top to form a crinkled crust. Sprinkle rosemary and thyme leaves on top, then bake for 30 to 45 minutes, or until crust is golden brown and veggies are tender.
*I like to buy beets pre-roasted, but to roast them yourself just drizzle with 1 Tbsp water and place in an aluminum foil pouch. Cook for 50 minutes at 375 degrees F, or until tender.