Heat a little canola oil in a cast-iron skillet over high heat until very hot. Sprinkle both sides of the rib eyes with granulated garlic, salt and pepper. Lower the heat to medium-high and place the rib eyes in the skillet without overcrowding. Sear the rib eyes until well browned, about 4 minutes. Flip the rib eyes and cook until medium/medium-rare, about 4 minutes. Set aside, loosely cover with foil and let rest. Mix the ricotta, Cheddar and provolone in a bowl and reserve.
Heat the vegetable oil in a large nonstick skillet over medium heat. Add the onions and sprinkle with salt and pepper. Sweat the onions until soft and slightly golden in color, about 10 minutes. Set aside. Thinly slice the rib eyes and set aside.
Divide the onions in 4 piles. Top each pile with a quarter of the cheese mixture, a quarter of the rib eye and an open roll. Let the cheese melt and toast until everything is gooey. Scoop up with a spatula, flip right-side-up and top each with the giardinera. Serve.