Soak the lentils in water for about 2 hours. Place them in a pressure cooker with a quarter of the onion, two garlic cloves, and a bit of coarse salt. Cook for about 10 minutes after the cooker reaches pressure.

Finely chop the remaining quarter onion. Cut the bacon, bell peppers, and potatoes into small cubes.

In a large skillet, cook the bacon with the onion. If needed, add a little olive oil. Cook until the onion is translucent. Add the bell peppers and potatoes and sauté for a few minutes.

Dice the tomatoes and add them to the skillet. Stir well, cover, and cook for 3 to 4 minutes. Add the cooked lentils and bring everything to a boil. Adjust salt to taste and remove from heat.