Source: Food Network Magazine
For the aioli:
1 cup mayonnaise
Grated zest of 1 lemon
1/3 cup fresh lemon juice (from about 3 lemons)
1/2 tablespoon dijon mustard
1/4 cup minced garlic (6 to 8 cloves)
For the mushrooms:
1 pound portobello mushrooms, stems and gills scraped out, cut into 1/2-inch strips
2 cups buttermilk
2 large eggs, separated
3/4 cup beer (preferably lager or pale ale)
3/4 cup all-purpose flour
3/4 cup white cornmeal
Kosher salt and freshly ground black pepper
1/2 teaspoon cayenne pepper
Peanut oil, for frying (about 6 cups)
Sea salt
Make the aioli: Combine the mayonnaise, lemon zest and juice, mustard and garlic in a food processor and process until combined. Transfer to a bowl, cover and refrigerate 1 hour before serving.
Meanwhile, prepare the mushrooms: In a shallow pan, soak the mushroom strips in the buttermilk, about 1 hour.
Make the batter: In a large bowl, combine the egg yolks, beer, flour, cornmeal, 1 teaspoon kosher salt, 1/2 teaspoon black pepper and the cayenne. Fill a large deep pot with about 1 1/2 inches peanut oil; heat over medium-high heat until a deep-fry thermometer registers 350 degrees F.
In a large bowl, beat the egg whites with a mixer until stiff peaks form. Gently fold the beaten egg whites into the batter. One at a time, dip the mushroom strips in the batter, then carefully lower into the hot oil. (Do this in batches if necessary-do not crowd the pot.) Fry until golden brown, 2 to 3 minutes, turning with tongs. Remove and drain on a paper towel-lined plate. Sprinkle with sea salt and serve with the garlic aioli.
