Adobo Beef and Mushroom Tacos - Lakewinds Food Co-op

Ingredients

• ¼ cup cider vinegar
• 1 Tablespoon sugar
• ¼ teaspoon coarse Kosher salt
• ½ medium red onion, <em>very thinly sliced</em>
• 1 pound lean (at least 80%) ground beef
• 2 containers (8 ounces each) sliced mixed mushrooms
• 2 chipotle peppers in adobo sauce, <em>finely chopped</em>
• 1 Tablespoon adobo sauce from the chipotle peppers
• 1½ teaspoons ground cumin
• ½ teaspoon chipotle Chile pepper
• 3 cloves garlic, <em>finely chopped</em>
• ½ teaspoon salt
• 3 Tablespoons tomato paste
• 16 small corn tortillas
• 1 medium ripe avocado,<em> thinly sliced</em>
• ¼ cup fresh cilantro
• Lime wedges, for serving
• Crumbled queso fresco cheese, for serving