Step 1

Heat the olive oil in a large pot or Dutch oven over medium-high heat until shimmering. Add the onion, bell pepper, garlic, 1/2 teaspoon salt and several grinds of black pepper. Cook until vegetables are just tender and browned in spots, stirring occasionally, about 6 minutes. Stir in the tomato paste, chili powder, oregano and cumin, then continue to cook until fragrant and brick-red in color, stirring frequently, about 2 minutes.

Step 2

Stir in the vegetable broth, diced tomatoes, beans (and their liquid), lentils, bay leaf, 1/2 teaspoon salt and a couple grinds of black pepper. Bring to a steady simmer, then reduce the heat to medium-low. Partially cover with a lid and gently simmer, stirring occasionally, until the lentils are tender and the chili has thickened slightly, 35 to 45 minutes.

Step 3

Remove the bay leaf and stir in the vinegar. Season with salt and black pepper. Ladle into bowls and serve with toppings as desired.