This is a frittata for someone who really likes mushrooms!
I used crimini and shitake mushrooms for this frittata, as these are readily available, but you could certainly use other kinds. I think using two different types adds to the complexity of the flavor. I definitely think this frittata calls for something more interesting than the white button mushrooms. By the way, the quantity of mushrooms may look like way to much for the frittata when you first put them into the pan, but remember that mushrooms cook down a great deal.
For me, 1/8 teaspoon of truffle oil (I used black truffle oil) is just enough to add to the flavor of the mushrooms. You may want more or less, so taste and smell the mushrooms as you add the oil. A note on truffle oil: Most (all?) truffle oil gets its flavor not from truffles but from the chemical that is the primary flavor component of truffles. It may or may not also have some real truffle included as well. When you think about it, given the extremely high price of truffles, there is no way real truffles could be used to get that much truffle flavor into a bottle of oil that could sell for under $15. Extreme disputes have arisen as to whether it is appropriate to use such artificially-flavored truffle oil in fine cuisine. Some chefs bitterly oppose its use. On the other hand, Thomas Keller’s French Laundry cookbook has numerous recipes that call for truffle oil.
In these blog posts I frequently describe the inspiration for a frittata or salad. When I first made this frittata, I wasn’t (consciously) thinking of any specific dish or recipe. This just seemed like something that would work and taste good. But as I was writing this post, I recalled what was surely the source for this. Some years ago, we had this absolutely awesome mushroom soup in a restaurant in Monterey, California. My daughter, an excellent chef, recreated the soup. The primary ingredients were mushrooms, cream, goat cheese, and truffle oil.
If you want to have a glass of wine with your frittata, this is very earthy, so I would suggest a red wine.
Mushroom truffle frittata
1 heaping cup crimini mushrooms, sliced
1 heaping cup shitake mushrooms, caps, sliced and cut into pieces
1/3 cup/1 ounce goat cheese, shredded or crumbled
1/8 teaspoon truffle oil
Cook mushrooms over medium to medium-low heat for 10 to 12 minutes, until the moisture is gone and they start to nicely brown. You may want to turn up the heat towards the end to help them brown. Several minutes before the mushrooms are done, add the truffle oil so it can be cooked through all of the mushrooms. Remove from the pan.
Put the eggs into a good-sized mixing bowl and beat just to mix them up. Add a bit of oil to the pan if needed and let it get hot. Add a small amount of the eggs to the pan to set the bottom of the frittata to prevent sticking. Turn the heat down to medium low. Mix the mushrooms and goat cheese into the eggs and pour the mixture into the pan. Cook this for about 5 minutes to set the bottom and sides.
Preheat the broiler. When the 5 minutes cooking on the stove are up, place the pan under the broiler, about 6 to 7 inches below. Cook until the top is set and just starts to brown. This is about 1–1/2 to 2 minutes for me, but watch closely.
Remove from the broiler, loosen up the sides with a spatula if necessary, and slide the frittata out onto the serving plate.