Rinse the shirataki noodles and blanch them briefly in boiling water to remove the odd smell. Drain well.
Mix the sugar, sake, soy sauce, and mirin in a bowl. Add the beef and marinate for 5–10 minutes while you prep the rest.
Cut the potatoes in half, carrot into bite-sized chunks, and onion into wedges. Keep the pieces large so they hold their shape under pressure.
Dissolve a dashi packet or teaspoon of dashi granules in 100ml of water.
Load the inner pot: vegetables first, then the marinated beef with its seasoning liquid, then shirataki noodles, then pour the dashi over the top.
Close the lid and set to high pressure for 4 minutes (or use the nikujaga preset if available).
After pressure has fully released, open the lid. Switch to simmer mode and cook uncovered for about 10 minutes to reduce the liquid. Top with snap peas and serve.