I always wash the peas first then pick through to get the bad ones out. I then soak them for a few hours. In a large pot, I add the peas (drained from the water they soaked in), chopped onion, some minched garlic, salt & pepper, a ham bone (or chunks of ham). I add just enough water to the pot to cover and bring to a boil. Then I turn down the heat to simmer and cook until tender.
The finished product is a thin bean consistency, if your mixture is thick just add small amounts of water until you have the consistency you want. I make some rice and we eat the beans over rice (Hoppin John) with buttermilk cornbread on the side. I also serve fresh collards.