Mushroom Tacos with Avocado-Tomatillo Salsa

We were in the mood for Mexican the other night but I wasn't quite up for time required to make enchiladas (even though they are so good). Tacos, however, are a great way to get a fresh, healthy, and relatively easy meal and are also something that's fun to play with because you can experiment with different toppings. For this version, I thought mushrooms would be an great and somewhat different base, and I also wanted to incoporate some of the fresh corn that's finally in season. Top it off with one of the easiest salsas that I've ever come up with and you've got one tasty taco. The salsa is also great as a dip for tortilla chips - it has a nice thick consistency. I made the full amount of everything here for the two of us and we just reheated the leftovers in a skillet the next day - they were just as good the second time around.

Mushroom Tacos with Avocado-Tomatilo Salsa
Serves 4 (three tacos each)
Active Time: 15 minutes
Total Time: 20 minutes

Taco filling:
Extra virgin olive oil
1 portabello mushroom (about 1/2 lb.), halved and thinly sliced
1/2 lb. white buttom mushrooms, thinly sliced
1/4 lb. oyster mushrooms, roughly chopped (or other wild mushroom of your choice)
3/4 of one yellow onion, halved and sliced
1 t. kosher salt, divided
Black pepper
1 bunch green onions, white and green parts, sliced into ~1/2'' pieces
2 ears corn, kernels removed
1 T. fresh oregano, finely chopped
12 small corn tortillas

Salsa:
2 small avocados, pitted, skin removed, and cut into quarters
2-3 tomatillos, skin removed, rinsed, and quartered
1 lime
1 serrano chile, stem removed, seeds left intact, roughly chopped
1 t. kosher salt
1/2 t. black pepper
1/2 c. diced yellow onion (remaining quarter of the onion used above)

Queso fresco cheese (for topping)

Heat 1 T. olive oil in a large skillet over medium-high heat. Add the onion and mushrooms, 1/2 t. kosher salt and a pinch of black pepper, and saute 4-5 minutes, stirring often, until both soften. Add the green onions, corn, and another 1/2 t. kosher salt and saute for another 3 minutes. Remove from heat and stir in the 1 T. fresh oregano.

Meanwhile, make the salsa by combining the avocado, tomatillos, juice of 1 lime, serrano chile, kosher salt, pepper, and onion in a food processor and processing until smooth. Put the stack of tortillas in between 2 damp paper towels and microwave for about 1 minute.

To assemble the tacos, spoon some of the mushroom-corn-onion mixture onto each tortilla, then top with a generous dollop of the avocado-tomatillo salsa and a crumbling of queso fresco cheese.