Vegetable Ceviche

Name: Vegetable Ceviche
Ingredients: One 8-ounce portobello mushroom cap, gills discarded, cut into 1/2-inch pieces; One 8-ounce sweet potato, peeled and cut into 1/2-inch pieces; 1/4 cup olive oil; 1 teaspoon ground cumin; Kosher salt and freshly ground black pepper; 3 ounces thin asparagus tips (from 1 small bunch); One 15-ounce can hominy, drained and rinsed; 1/4 red onion, thinly sliced, plus more for serving; 1/2 lemon; Leche de Tigre, recipe follows; Inka or corn nuts, for serving; Fresh cilantro leaves, for serving; Blue corn tortilla chips, for serving; 3/4 cup lime juice; 1/4 cup coconut milk; 2 tablespoons jarred aji amarillo paste; 2 tablespoons roughly chopped fresh cilantro; 2 tablespoons olive oil; 1 clove garlic, roughly chopped; One 1-inch piece fresh ginger, roughly chopped; Kosher salt