In a deep fryer or large saucepan, heat oil over medium heat to 350°F.
With a small round cookie cutter, cut holes in the center of each biscuit. Place 3-4 biscuits in the heated oil. Let one side cook until golden brown (about 1 minute). Flip over and let the other side cook until golden brown. Remove from oil and place on a cooling rack.
In a medium saucepan, heat the milk and vanilla on low heat until warm. Remove from heat and whisk in the powdered sugar until fully combined.
Dip the donuts into the glaze and place them back on the cooling rack to set up for 2-3 minutes. When the first layer of glaze has set up, dip the donuts a second time and add desired sprinkles/toppings before serving.