Source: https://www.youtube.com/watch?v=PmKGAW0JFsI&list=PLlTui5SiwlWREB7ZwRw2-75e5YxXfkfJx&index=55

Ingredients

2 pounds Yukon Gold potatoes
1⁄2 small red onion or 2 shallots
2 lemons
1 bunch parsley or dill
Kosher salt and freshly ground black pepper
1⁄3 cup extra-virgin olive oil, plus more for drizzling

Instructions

Potatoes

Clean potatoes and cut into large pieces, about 4 per potato. Aim for even size across all of them so they cook at the same rate. Put in pressure cooker container and submerge fully in water. Add about 1/4-1/3 cup kosher salt. Cook on high pressure for 5 minutes. Allow the pressure to naturally release for 5 minutes and let off the excess steam. Use a fork or knife to test potatoes for doneness.

Place potato pieces on a paper towel lined tray to drain.

Pickled Onions

Slice onion thinly and soak in cold water for 5 minutes. Drain onions well.
Add about 1 tsp of kosher salt to the onions along with the juice from one whole lemon. Stir well and macerate slightly so the onions are lightly bruised and absorb more of the liquid.

Assembly

Finely chop the herbs.
Break potatoes into large pieces and add a layer to a bowl. Drizzle olive oil over the potatoes and gently fold until well coated. Add another layer of potatoes and cover in olive oil. squeeze a bit of lemon juice on as you go. Once all potatoes are in the bowl, add chopped herbs, pickled onions along with the lemon juice. Gently fold and stir until well combined.

Serve warm or cold the next day.