Coconutty Beans and Greens Stew

Name: Coconutty Beans and Greens Stew
Ingredients: 1 medium onion, coarsely chopped; 1 plum tomato, coarsely chopped; 3 garlic cloves; 1 1" piece ginger, scrubbed; 2 red Thai chiles or 1 Fresno chile; 3 Tbsp. extra-virgin olive oil, divided, plus more for serving; 2 tsp. Diamond Crystal or 1 tsp. Morton kosher salt, divided, plus more; ½ tsp. ground coriander; ½ tsp. ground cumin; 1 13.5-oz. can unsweetened coconut milk; 1 medium sweet potato, peeled, sliced into ¼"-thick rounds; 1 large bunch Swiss chard or Tuscan kale, ribs and stems removed, leaves coarsely chopped; 2 15-oz. cans butter, gigante, or cannellini beans, rinsed; 2 Tbsp. (or more) fresh lemon juice; 1 baguette, sliced on a diagonal 1" thick; Flaky sea salt