Step 1
Prepare and Brine the Oyster Mushrooms. Trim the tough root end of the oyster mushroom cluster using kitchen shears, keeping the cluster intact. Place the mushrooms in a dish and cover with pickle juice.Allow to brine for 1 hour, ensuring full flavor absorption and tenderness.
Step 2
Set Up the Breading Station: In the first bowl, add the all-purpose flour for the initial coating. In the second bowl, whisk the eggs. In the third bowl, mix the remaining flour, cornstarch, garlic powder, salt, and pepper.
Step 3
Bread the Mushrooms: Remove the mushrooms from the brine and pat them dry slightly. Dip the mushroom cluster into the first bowl (dry flour), coating every crevice. Next, submerge the mushroom into the egg mixture, ensuring even coverage. Transfer to the final bowl (flour and cornstarch mix) and coat thoroughly.
For extra crispy bits, drizzle a small amount of egg into the final flour mix, creating small clumps that can stick to the mushroom.
Step 4
Fry the Mushrooms: Heat oil in a deep fryer or heavy-bottomed pot to 375°F (190°C). Carefully fry the breaded mushroom for about 4 minutes until golden brown and crispy. Transfer to a wire rack and season immediately with a pinch of salt.
Step 5
Make the Garlic Aioli: In a tall container, combine olive oil, the whole egg, grated garlic, and mustard. Insert an immersion blender to the bottom of the container, then blend while slowly pulling upward. The aiolishould thicken in 15 seconds. Season with salt to taste and add a splash of lemon juice or vinegar for brightness.
Step 6
Assemble the Sandwich: Spread a generous layer of garlic aioli on the bottom half of the toasted bun. Add a bed of fresh spinach or lettuce. Place the crispy oyster mushroom on top of the greens. Optionally, drizzle more aioli on top before capping with the bun lid. Secure with a skewer for presentation.
