Soak kidney beans in large bowl with enough cold water to cover by 3 inches, at least 4 hours or overnight. Drain.
Place 2 quarts water, beans, ham, potato in large pot.
Saute onion, pepper, and garlic in about 1 tsp olive oil. Add to beans.
Stovetop method
Bring to boil over medium-high heat. Reduce heat to medium, cover and simmer until beans are tender, stirring occasionally, about 50 minutes. Season to taste with salt.
Pressure Cooker Method
Pressure cook over med heat for about 45 minutes. Wait until pressure is released before removing lid. Season to taste with salt.