In a bowl, combine Mazola Corn Oil, sea salt, lemon zest and garlic to create marinade.
Slice mushrooms, squash, zucchini, bell peppers, and onion and add to marinade. Toss to coat. Cover and refrigerate for 30 minutes.
Line your grill with a large sheet of foil or use a baking pan or griddle. Heat grill to high then add marinated veggies. You'll want to stir the vegetables occasionally as they cook. Grill for about 15 minutes or until veggies are softened and a bit charred.
Prepare the lemon-garlic aioli sauce by simply mixing together the ingredients in a small dish.
Slice the ciabatta rolls in half and toast lightly on the grill or in the toaster.
Layer grilled veggies on top of the toasted rolls, then top with feta cheese crumbles. Spoon on lemon-garlic sauce and you're ready to serve!