Place 1 chopped yellow onion into a food processorĀ
Pulse until very finely diced
Transfer into a fine kitchen towel or cheesecloth and strain excess liquid from the diced onion
Transfer the strained onion into a medium bowl and add the remaining ingredients
Mix until everything is fully combined
Cover the bowl with plastic wrap and refrigerate for 60 minutes
Pulse the meat mixture into a thick paste like texture in a food processor (1/3 of the batch at a time) and layer the meat into a 9"x5" loaf pan
Preheat your oven to 325 degreesĀ
Bring a pot of water to a rolling boil
Place a large kitchen towel into a 9"x13" cake pan and place the filled loaf pan over the towel in the center of the cake pan
Add enough boiling water into the cake pan to come 1/2 the way up the sides of the loaf pan
Very carefully transfer the pans into a preheat oven on a middle rack
Bake at 325 degrees for 50-60 minutes
The meat is done when the internal temperature reaches 165 degrees
Carefully remove the pans from the oven and remove the loaf pan from the cake pan
Pour any liquid fat from the loaf pan and place the pan onto a wooden cutting board
Place a foil covered brick over the meat and allow it to cool and compact for 20 minutes
Transfer the meat out of loaf pan and wrap it tightly in plastic wrap and tin foil
Refrigerate the wrapped meat for 2-24 hours
Unwrap the meat and cut 1/4 inch slices
Grill on a flat griddle or large skillet over medium high heat until both sides are browned and crispy
Assemble your gyros by placing slices of meat on a piece of flatbread and topping with tzatziki, onions and tomatoes