Portabella Stuffed Burger topped with avacado goat cheese spread - Sutter Home Family Vineyards

Ingredients

• 4-5 Portabella mushroom caps sm. dice
• 3/4 cup balsamic vinegar
• 1 tbs. olive oil
• 1 med. white/or vidalia onion sm.dice
• 2 tbs. seasoning mix
• 2 lbs. ground sirloin
• 3/4 cup parmesan cheese
• 6 sourdough rolls
• 3 plum tomatoes (sliced)
• 1 bunch baby spinach
• 2 avocado 4-6 oz.
• creamy goat cheese
• juice of 1/2 lemon
• 1 1/2 tsp. seasoning mix