Melted Mushroom & Onion Cauliflower Steaks

1 head cauliflower                     
2 tbsp. olive oil, or as needed, divided
1/2 cup water                     
1 onion, chopped     
1 cup sliced baby bella mushrooms                 
3 oz. organic cheddar cheese, shredded

Trim the stem and edges from the cauliflower so that the head more resembles the shape of a square.  Cut cauliflower into 3 or 4 thick “steaks.”  Reserve any florets that have fallen off while slicing steaks.

Heat 1 tablespoon olive oil in a large skillet over medium heat.  Satué cauliflower steaks in the until browned, 3 to 4 minutes per side.  Add florets and water to skillet; cover and steam until cauliflower is tender, 10 to 15 minutes.

Heat remaining 1 tablespoon olive oil in a separate skillet over medium heat; sauté onion about 2 minutes.  Add mushrooms and sauté until onion is lightly browned and mushrooms are tender, 10 to 15 minutes.

Set oven rack about 6 inches from the heat source and preheat the oven's broiler.

Arrange cauliflower steaks and florets on a parchment-lined baking sheet; top with onion-mushroom mixture and shredded cheddar cheese.

Broil in the preheated oven until cheese is melted, and serve immediately.