Combine chopped potatoes, onions and garlic in a microwave safe bowl and microwave for 2~3 minutes or until the veggies are fork tender.
Drain the veggies and place them in a 8" or 9" baking dish. Drizzle with oil, salt and pepper. Toss to coat and put the baking dish in the oven.
Bake for 25~30 minutes or until the potatoes are crispy.
In the meantime, combine the three cheeses. Once the potatoes turn crispy, sprinkle the cheese mix on top and bake for another 4~5 minutes or until the cheese melts and gets ooey & gooey. Serve immediately and Enjoy!!