Marinated Raw Mushrooms

Ingredients

• 1 lb. fresh, small, white mushrooms
• 1 red onion, sliced into rings
• 2/3 c. white vinegar
• 1/4 c. water
• 2 Tbsp. olive oil or other salad oil
• 1 clove garlic, minced
• 1 1/2 tsp. salt or garlic salt
• 1/4 tsp. pepper, coarsely ground
• pinch of cayenne pepper (optional)