Instant Pot broccoli and cheese orzo

This broccoli cheese orzo is reminiscent of those broccoli and rice casseroles held together with cream of mushroom soup, except, we're basically making our own mushroom cream. The Instant Pot is great for making one-pot pasta and veggie meals, especially cheesy ones. Because the starchy pasta liquid isn't drained away, it makes the perfect substitute for a roux. You can stir cheese in at the end and it emulsifies perfectly with the extra starch. This is perfect adult comfort food that I'm sure kids would love, too!

Instant Pot broccoli and cheese orzo
2 T butter
1 medium onion, diced
~6 oz sliced mushrooms (optional, but really good)
1 T minced garlic

1 lb orzo pasta

1 t Tony Chachere's seasoning or salt
1/2 t thyme (optional)

Black pepper to taste
5 cups water

1 T Better than Bouillon (I like mushroom or "no chicken" flavor here)
1 lb frozen or fresh broccoli florets (if using frozen broccoli, no need to thaw)
6 oz shredded cheddar
1/4 cup grated parmesan
2 t lemon juice (optional; adds a subtle hint of acid to make flavors pop)

In the Instant Pot, saute onion and mushrooms (if using) in butter until translucent. Add garlic and orzo and toast for a couple of minutes, stirring frequently. Stir in remaining ingredients except cheese and lemon. Seal the Instant Pot and set to pressure cook for 1 minute. When finished cooking, do a quick release. Stir in the cheeses and lemon juice (if using) and serve. Serves 6.