Using a pair of tongs, flame roast the tomatillos until they are lightly charred on all sides. Place them in the bowl of a food processor.
Char the jalapenos the same way. Once cooled, trim off the stem and remove the seeds and ribs. Dice the peppers and add to the food processor.
Add onion, cilantro, the juice of 1 lime, and a generous pinch of salt to the food processor and pulse until it’s pureed. Adjust salt if needed.
In a small pan, add the olive oil and sauté the garlic over medium heat until it's golden brown. Remove from the heat. Stir it into the tomatillo puree until the oil incorporates. Add a pinch of cumin and 2 Tbl. fine diced red onion.
Split the avocados, remove the pit, then using a large spoon scoop out flesh from each half. Cut flesh into 1/4" to 1/2" sized cubes. Sprinkle with a little lemon juice to keep them from turning brown. Season with salt. Gently fold into the salsa. Garnish with fresh cilantro leaves.