Using a large bowl, add beans and cover with at least 4” of cold water. Cover bowl with plastic wrap and let stand at room temperature overnight.

The next day, drain and rinse beans. Transfer beans into a large pot and cover with at least 2” of water. Cover pot and bring to a boil over high heat. Reduce heat to medium-low and let simmer uncovered for 45 minutes.

Add 2 tsp of kosher salt and continue simmering for 10 more minutes.

Preheat oven to 325°F.

Meanwhile, using a large skillet, cook the bacon until crispy. Transfer bacon to a paper-towel lined plate and pat dry. Do not drain bacon grease from skillet.

Add diced onions to skillet and sauté over medium-low heat for 5-6 minutes, stirring occasionally, or until onions are golden brown in color.

Using a colander, drain beans, but reserve the cooking liquid.

Using a large bowl, add beans, onions, bacon, ketchup, maple syrup, dry mustard and black pepper; stir until well combined.

Transfer beans into a Dutch oven or oven-safe pot. Add enough cooking liquid to barely cover beans. Cover pot and bake for 2 hours. (Note: Check beans after 1 hour. If beans appear dry, add more of the reserved cooking water until beans are barely covered.)

Uncover and continue baking for 60-75 minutes, or until cooking liquid has thickened and beans have turned golden brown. (Note: If beans appear dry, add a small amount of cooking water as needed.)