Ingredients
6 radishes, very thinly sliced
2 tablespoons white vinegar
Coarse salt and freshly ground pepper
1/4 cup extra-virgin olive oil
2 large poblano chiles, stems and seeds removed, thinly sliced
2 medium onions, thinly sliced (3 cups)
1/4 medium kabocha squash, peeled and cut into 1-inch pieces (2 cups)
1/2 teaspoon chopped fresh oregano, plus small leaves for serving
6 to 8 tostada shells
Sour cream and Cotija cheese, for serving
Preparation
Toss radishes with vinegar in a bowl. Season with salt; let stand.
Meanwhile, heat oil in a large straight-sided skillet over high. Add chiles and cook, stirring, 1 minute. Add onions and cook, stirring occasionally, until translucent, about 5 minutes. Stir in squash and season with salt and pepper. Cook, stirring, 1 minute. Stir in oregano.
Add 2/3 cup water. Cover, reduce heat to medium, and cook, stirring once or twice, until squash is tender and almost all liquid is absorbed, about 6 minutes.
Spread tostada shells with sour cream. Top with squash mixture and pickled radishes, dividing evenly. Drizzle with some of pickling liquid. Sprinkle with cheese and oregano leaves; serve.
