Tex-Mex vegetable fajitas with cheesy refried beans and sazón-spiced yogurt

• Peel and thinly slice enough onion to measure 1½ cups [3 cups].
• Remove the stems and seeds from the sweet mini peppers; cut the peppers lengthwise into ¼-inch-wide strips. 

In a large frying pan over medium-high heat, warm 1 to 3 teaspoons oil until hot but not smoking. Stir in the onion and cook until starting to brown, 1 to 2 minutes. Add the sweet mini peppers, season with salt and pepper, and cook, stirring occasionally, until starting to brown and soften, 4 to 5 minutes. Transfer to a plate. Wipe out the pan if using for the tortillas. While the onion and peppers are cooking, prepare the lime and start the refried beans.

• Juice ½ lime [1 lime] and set aside for the yogurt sauce. Cut the remaining ½ lime [1 lime] into wedges for serving. 
• Rinse the pinto beans.

In another large frying pan over medium heat, combine the beans and ¼ cup [½ cup] water and season with salt and pepper. Bring to a boil, then reduce to a simmer and cook, gently mashing the beans into a coarse paste, until heated through, 2 to 3 minutes. Stir in the tomatillo simmer sauce and cook until heated through, 1 to 2 minutes. Stir in the Mexican cheese blend and remove from the heat. Season to taste with salt and pepper.

While the beans are cooking, heat the tortillas and make the sazón yogurt.

On the stovetop directly over a flame, or in the same pan used for the onion and peppers over medium heat, warm the tortillas, turning once, until just pliable and warmed through, about 30 seconds per side. Transfer to a clean kitchen towel, cover, and keep warm.

In a small bowl, stir together the yogurt, sazón seasoning, and lime juice. Season to taste with salt and pepper. 

Set out the tortillas, onion and peppers, refried beans, sazón yogurt, and lime wedges. Invite everyone to assemble their own fajitas.