Make the avocado sauce: Blend avocado, sour cream, lime juice, and cilantro if using in a blender or small food processor until smooth. Thin with water if needed. Refrigerate until ready to serve.

Cook ground beef, onion, garlic, and jalapenos in a large skillet over medium-high heat, breaking up the meat. Cook until browned and vegetables are translucent. Drain excess fat if needed.

Add all spices and stir, cooking until fragrant, about 30 seconds. Remove from heat and stir in salsa and shredded cheese. Let cool a few minutes.

Lay a tortilla flat. Spoon about 1/4 cup meat mixture across the lower third. Roll tightly from the bottom into a cylinder. Place seam-side down. Repeat with remaining tortillas and filling.

Heat oil in a skillet over medium-high. Fry flautas seam-side down first to seal, then turn to brown all sides until golden and crispy. Drain on paper towels. Serve with avocado sauce, extra cheese, and sour cream.