01 -
Preheat the Blackstone grill to medium-high heat (around 400°F) and evenly spread vegetable oil over the surface to prevent sticking.
02 -
Place diced steak and onions on the grill in a single layer. Season with onion powder, salt, and pepper. Cook for 4–8 minutes per side until well browned with crisp edges.
03 -
Move cooked steak and onions to one side of the grill. Reduce heat to medium to prepare the surface for quesadilla assembly.
04 -
Place tortillas on the cleared grill area. Add a layer of mozzarella and Monterey Jack cheeses, followed by the steak and onion mixture, then top with more cheese.
05 -
Fold each tortilla in half to form a half-moon shape. Cook for 1–2 minutes until golden brown on the bottom.
06 -
Flip each quesadilla and grill the other side for 1–2 minutes until golden and crispy.
07 -
Transfer quesadillas to a cutting board, slice into wedges, and serve immediately while hot and melty.