Instructions:
- Whisk together vinegar, oil, garlic powder, salt and pepper in a small bowl.
- Put vinegar mixture and clean mushrooms in a large, resealable plastic bag and shake to coat. Let marinate for at least 30 minutes at room temperature or up to four hours in the refrigerator, turning occasionally.
- Preheat grill to medium-high heat. Gently shake off excess marinade and grill mushrooms for 4-5 minutes per side. Cool briefly, then slice mushrooms.
- Preheat broiler. Place ciabatta slices on sheet pan. Evenly divide mushroom slices on ciabatta.
- Top each piece of ciabatta with two slices of Kerrygold Swiss Cheese. Broil until cheese melts.
- Top each toast with arugula and pickled red onions. Drizzle with grainy mustard and sprinkle with flaky sea salt.
Pickled Red Onions:
- Place vinegar, sugar and salt in a small saucepan and cook over medium-high heat for 3 minutes or until sugar dissolves, stirring occasionally.
- Place peppercorns and onions in a jar or other lidded container. Pour hot vinegar mixture over onions and cool to room temperature. Cover and refrigerate until ready to use.
NOTE: onions will keep for up to 3 weeks in the refrigerator.
Recipe by Garnish with Lemon