• Pat the chicken dry with a paper towel; season generously with salt and pepper and as much spice rub as you like. Let stand until ready to cook.

• Peel and finely chop enough red onion to measure ½ cup.
• Remove the husks from the tomatillos; rinse, pat dry, and coarsely chop the fruit.
• Cut the cherry tomatoes in half or into quarters.
• Cut the avocado in half. Remove the pit, scoop out the flesh, and cut the flesh into bite-size pieces.
• Finely chop, press, or grate enough garlic to measure 1 teaspoon.
• Juice half the lime; cut half into wedges for garnish.
• Coarsely chop the cilantro; set aside half for garnish.

In a medium bowl, stir together the onion, tomatillos, tomatoes, avocado, garlic, lime juice, half the cilantro, and 2 to 3 teaspoons oil. Season to taste with salt, pepper, and as many chile flakes as you like.

In a large frying or grill pan over medium-high heat, warm 1 to 2 teaspoons oil until hot but not smoking. Add the chicken and cook until slightly browned, 1 to 2 minutes per side. Reduce the heat to medium-low and continue cooking, turning occasionally, until firm and cooked through, 5 to 8 minutes, depending on thickness. Transfer to a plate to rest for 5 minutes. Do not clean the pan.
While the chicken cooks and rests, prepare the asparagus.

• Snap off the woody ends from the asparagus.

In the same pan used for the chicken, add the asparagus, season lightly with salt and pepper, and cook over medium-high heat, turning once, until just starting to soften, 1 to 2 minutes. Add ¼ cup water and cook, turning once or twice, until crisp-tender, 2 to 3 minutes longer. Drain and pat dry.

Transfer the chicken and asparagus to individual plates. Top the chicken with the tomatillo-avocado salsa, garnish with the remaining cilantro, and serve with the lime wedges.

Make It Leaner: The oil in the salsa adds flavor, texture, and good fats but also bumps up the calories. You can lose 60 calories by omitting the oil altogether. To brighten the salsa while keeping calories to a minimum, add some additional lime juice and chile flakes.