Meanwhile combine melted plant butter, harissa paste, lemon juice, garlic powder, onion powder and oregano.
Brush all the harissa butter over the two cauliflower steaks, being sure to get all the crevices!
Season each side of the cauliflower steaks with salt.
Reduce grill heat to medium high/medium and place cauliflower steaks on and close the lid.
Let cook for 10 minutes, flip and let cook with the lid closed for 10-13 minutes longer. Pierce with a fork to test for doneness.
Serve with grilled veggies and roasted sweet potatoes or put it on a sandwich!