Heat the oven to 450 degrees and line a sheet pan with parchment paper.
Prepare eggplants by slicing off their tops and a fine layer of skin from their bottoms. Slice the eggplant into 1-inch-thick rounds and place on the lined pan.
Make your spice oil by combining the olive oil, garlic, cumin, salt and red pepper flakes in a small bowl. Brush the spiced oil onto the faces of all the eggplant slices, then flip each one over and repeat on the second side.
Roast for 20 minutes, then use a spatula to flip over each round. Roast for another 10 to 20 minutes, or until soft, browned and crisp. If you’re looking for a little extra color, broil the eggplant, watching carefully, for about a minute.
