Makes 1 1/2 cups to use as a potato salad dressing
3 egg yolks
2 tsp white wine vinegar
1/2 tsp salt
1/2 tsp dijon mustard
1 cup olive oil
3 tsp boiling water
3 tsp capers
1 gherkin, chopped
500g waxy potatoes
1 small red onion, finely sliced
1 Put the yolks, vinegar, salt and mustard into the bowl of a food processor. Whisk until combined.
2 With the motor running, drizzle in the olive oil until the mayonnaise is thick then add the boiling water.
3 Add the capers and gherkin then stir to combine.
