Ingredients

• 2 15-ounce cans pinto beans (preferably organic), liquid drained and reserved
• 1/2 cup chopped white onion
• 2 tablespoons dried oregano
• 2 garlic cloves, peeled
• 2 teaspoons minced canned chipotle chiles in adobo
• 1 teaspoon ground cumin
• 1 tablespoon extra-virgin olive oil
• Coarse kosher salt
• 1 large fresh fennel bulb, trimmed, cut through core into 1/3-inch-thick slices (some slices will separate)
• 6 tablespoons safflower oil, divided
• 4 skinless boneless chicken breast halves
• 1/3 cup coriander seeds (about 1 ounce), coarsely crushed in plastic bag
• 6 purchased corn tostada shells
• 3 cups thinly sliced romaine lettuce
• 6 radishes, trimmed, thinly sliced
• 6 fresh cilantro sprigs
• Lime wedges
• Ingredient info: Chipotle chiles are often sold in a spicy tomato sauce called adobo. They're available at some supermarkets and at specialty foods stores and Latin markets.

Instructions

1. Place beans and next 5 ingredients in processor; blend to chunky puree.
2. Heat oil in heavy large saucepan over medium heat. Add bean mixture and 1/2 cup reserved bean liquid. Stir over medium- low heat until warmed through, adding more bean liquid if dry, about 5 minutes. Season with coarse salt and freshly ground black pepper. DO AHEAD: Can be made 1 day ahead. Cover; chill. Rewarm before using.
3. Brush fennel slices with 1 1/2 tablespoons oil; sprinkle with salt and pepper. Heat heavy large skillet over medium-high heat. Add fennel slices. Sear until lightly browned and crisp-tender, 2 to 3 minutes per side. Transfer to plate. Cut into strips. Reserve skillet.
4. Using rolling pin, flatten chicken between sheets of plastic wrap to 1/4- to 1/3-inch-thick cutlets. Spread out coriander seeds on sheet of foil. Sprinkle chicken with salt and pepper; coat with coriander seeds.
5. Heat 4 1/2 tablespoons oil in reserved skillet over medium-high heat. Working in batches, if necessary, add chicken to skillet. Sauté until cooked through, about 3 minutes per side. Transfer to work surface. Cool 5 minutes. Cut chicken in half lengthwise, then crosswise into 1/3-inch-wide strips.
6. Top each tostada shell with beans, lettuce, radishes, fennel, chicken and cilantro sprig. Serve with lime wedges.