Prep enchilada sauce: Preheat oven to 425°F. Remove any papery husks from tomatillos, then wash and chop. Finely chop 1 tortilla and place in a heatproof bowl. Add 3 tablespoons boiling water to chopped tortilla and stir. Cover and let stand until absorbed, about 5 minutes. Wrap remaining tortillas in foil.
Make sauce: Heat 1 tablespoon oil in a small saucepan over medium. Add tomatillos and cook until beginning to break down, about 5 minutes. Add 1 cup water and vegetable broth concentrate; bring to a boil. Cook until slightly reduced, 5–7 minutes. Stir in chopped tortillas and simmer, mashing, until thickened, about 4 minutes. Season with 1⁄4 teaspoon salt.
Prep ingredients: Meanwhile, coarsely grate or finely chop cheese. Trim ends from scallions and thinly slice. Rinse and drain beans. Halve jalapeño, then remove stem, seeds, and finely chop. Finely chop baby spinach. Wash and thinly slice radishes. Halve lime; juice half and cut the other half into wedges.
Make filling: Heat wrapped tortillas in oven until warm and pliable, about 5 minutes. In a large bowl, lightly mash beans with a spoon. Stir in spinach and half each cheese and scallions. Add half or all of the jalapeño, depending on your heat preference. Season with 1⁄2 teaspoon salt and a few grinds pepper.
Bake enchiladas: Lightly oil a small baking dish. Spread 1⁄2 cup of enchilada sauce on the bottom. Spoon about 1⁄2 cup of filling into each tortilla. Roll up and place in baking dish, seam side down. Pour remaining sauce over enchiladas and sprinkle with remaining cheese. Bake until bubbling, 18–20 minutes.
Make radish salad: In a medium bowl, toss radishes with 1 teaspoon each lime juice and oil. Add remaining scallions. Season to taste with salt and pepper. Serve enchiladas with lime wedges for squeezing over and with salad alongside. Enjoy!