In a large deep skillet or saucepan, melt 1 tablespoon of unsalted butter on medium-high heat on the stovetop until glistening. Add in your sage leaves to fry for 20 to 30 seconds. Transfer to a paper towel-lined plate. Season with kosher salt, just a pinch. Set aside until serving.
In the same pan, bring the heat to medium-high, add in your remaining tablespoon of butter to melt, add in your mushrooms, and saute until they brown, about 6 to 7 minutes, stirring occasionally. Season with salt. Remove some of your crispy mushrooms for topping (about 1⁄2 cup!)
Bring the heat to medium. Add the shallot and garlic and cook for 2 to 3 minutes until translucent, you don’t want to get any color on this. Season with kosher salt, black pepper and stir.
Add in your orzo, stirring frequently to combine with the mushrooms, then pour in your white wine and cook until completely reduced, for 1 minute.
Add in your warmed broth 1/2 cup at a time, stirring as you go, constantly, until it gets completely absorbed, and repeat in batches, until you have no more broth, about 15 to 20 minutes.
Finish with your cheddar cheese, tossing completely, until completely incorporated and melted. Season with kosher salt and black pepper, to taste.
Serve in bowls topped with your reserved mushrooms and crispy sage.