Fried Portobello Po\u2019boys
2 cups buttermilk, plus more as needed
2 tablespoons Cajun seasoning  
2 6-ounce packages sliced portobello mushrooms  
1 cup all-purpose flour
1 teaspoon baking powder  
Kosher salt and freshly ground pepper
Vegetable or canola oil, for frying
1/3 cup extra-virgin olive oil
1/4 cup apple cider vinegar
3 tablespoons Dijon mustard
1 tablespoon sugar
1 teaspoon mustard seeds
1 clove garlic, minced
Kosher salt and freshly ground pepper
1 16-ounce bag shredded coleslaw mix
2 cups shredded red cabbage
1/2 cup sliced scallions
2 tomatoes, thinly sliced
Dill pickle slices, for topping
2 baguettes or long loaves French bread, split open, lightly toasted and buttered
1 red onion, thinly sliced
Instructions:
Marinate the mushrooms: Whisk the buttermilk and 1 tablespoon Cajun seasoning in a large bowl, then add the portobellos and toss to coat. Refrigerate for 4 hours.
About 30 minutes before frying, make the slaw: Whisk the olive oil, vinegar, mustard, sugar, mustard seeds, garlic, a pinch of salt and a few grinds of pepper in a bowl. Add the coleslaw mix, red cabbage and scallions; toss lightly. Season with salt and pepper to your liking. Refrigerate until ready to serve.
Bread the mushrooms: Combine the flour, remaining 1 tablespoon Cajun seasoning, the baking powder and a pinch each of salt and pepper in a large shallow dish. Remove the mushrooms from the buttermilk marinade and coat in the seasoned flour (you can also shake the mushrooms with the seasoned flour in a paper bag). Shake off any excess flour and transfer the breaded mushrooms to a large plate.
Fill a large cast-iron skillet halfway with vegetable oil and fit the skillet with a deep-fry thermometer; heat the oil to 350˚ F. Line a baking sheet with paper towels and set a rack on top.
Add 6 to 8 mushroom slices to the hot oil and cook 3 to 4 minutes, then flip and cook until golden brown, 2 to 3 more minutes. Remove to the rack. Repeat with the remaining mushrooms.
Make the sandwiches: Lay the tomatoes and pickles on the bottoms of the bread, then top with the fried mushrooms, red onion and slaw. Close the sandwiches and cut each loaf in half.
