Peel the potatoes and chop into quarters. Boil in enough water to cover completely, then test with a skewer and make sure it goes through.
Drain the water from the pot (Step 1). Roast the potatoes for 1 minute to evaporate excess moisture. Crush into bite-sizes with a spatula or similar.
Combine all the [A] ingredients with the cooked potato and mix thoroughly. Set aside to cool slightly.
Thinly slice the cucumber, onion, and carrot with a slicer. Chop into bite-sized pieces or thin rounds.
Add 1 teaspoon of salt to the sliced vegetables from Step 4 and toss to mix in the salt thoroughly. Set aside for 10 minutes and drain well.
After the potato has cooled down, add the tossed vegetables and [B] ingredients. Mix well to serve.
Also good on bread.
Story Behind this Recipe
I wanted to think of a potato salad with lots of cucumber that's also good with bread. The key is to add grainy mustard.
Make sure to add the vinegar, wiener sausages, and coarsely ground black pepper while the potatoes are still hot. I usually make a large amount to serve in a sandwich the following morning. It's really delicious.