Place the potatoes in a large pot and cover with water. Add a large pinch of salt. Place over a medium-high heat and bring to a boil. Turn the heat down to a simmer and leave until the potatoes are fully cooked. I find it usually takes about 20 minutes from start to finish, however this will depend on the size of your potatoes. You know they are cooked when a knife inserts easily into the potato.
Using a slotted spoon, remove the potatoes. Return the water to a boil and add the trimmed green beans. Boil, uncovered, until the beans are cooked but still hold their shape, about 4 minutes. Drain the beans and set aside.
To serve, assemble the potatoes and beans on a serving platter. Top with the ricotta cheese, a few twists of salt and pepper and a good drizzle of olive oil. I like to serve this salad room temperature, except for the ricotta which should be cold.
You can cook the beans and potatoes in advance if you would like.