Place the oil in a skillet over medium heat and allow it to warm. When the oil is hot add 1/2 cup of the vegetable mixture. Use a spatula to mash it down a bit and give round-cake form. Let cook for 2-3 minutes, or until golden, turn and cook the other side. Remove from pan carefully and place on a plate with paper towels to absorb excess fat. Repeat the same procedure with the remaining mixture.