Bring 2 cups beans, 2 quarts stock, and 4 thyme sprigs to a gentle simmer in a medium pot over medium-high heat. Reduce heat to medium-low and simmer, uncovered, skimming any foam from surface, until beans are tender, 1-1 ½ hours, depending on types (After 1 hour, taste a few beans and cook longer if needed).
Discard the thyme stems, season liberally with black pepper, to your liking, remove from heat, and let sit 30 minutes.
At this point if you don't want to add cream, the beans can be seasoned with salt/pepper or other herbs and then added thyme and oil. But for a creamy, pretty dish, read on:
Return to a low simmer and stir in ½ cup cream. Season with kosher salt and more pepper, if needed. Serve topped with thyme leaves, sea salt, and drizzled with oil.
For a hearty, meaty dish, add chunks of uncured ham that you sear for added flavor, or cook some thick pepper bacon or black forest bacon and serve with two pieces placed in an X over the top of beans for nice presentation.
Be sure to include some crusty, chewy bread for dipping.