Defrost broccoli, asparagus, and green beans (if frozen) in a colander and shake to remove excess water.

Preheat a large frying pan. Slice the duck fry into one-inch (two and one-fourth-centimeter) slices. Fry duck fry until crispy. Remove with a slotted spoon and transfer to a paper towel.

Melt margarine in the same frying pan. Add garlic and allow to become fragrant, about 30 seconds. Next, add the veggies and toss to coat.

Add the maple syrup and continue stirring. Add the brown sugar, salt, pepper, and pepper flakes.

Remove from heat and stir in the crispy duck fry.