Place bacon in a Dutch oven over medium-high heat. Saute, turning occasionally, until slightly crispy, 5 to 6 minutes. Drain bacon slices on paper towels; reserve 3 tablespoons bacon grease and discard the rest.

Add a 1/4 cup of water to the pan and bring to a boil, scraping up all browned bits until water has evaporated. Add the reserved bacon grease, along with the green onions. Saute until softened, 3 to 4 minutes. Stir in brown sugar, about 1/4 cup at a time, cooking until sugar begins to brown, about 5 minutes.

Stir chili sauce into the pot and cook for 2 to 3 minutes. Pour in pork and beans, kidney beans, and lima beans; stir until beans are well coated in the sauce.

Return bacon to the pot and stir well to combine. Cover and reduce heat to low. Simmer, stirring occasionally to prevent burning, until flavors combine, 1 1/2 to 2 hours.