Using steamable bagged potatoes saves time and makes prep quick and easy. Then just toss them with a simple dressing and toss in charred onions for a sweet and smoky flavor.
For the onions:
Heat a grill to high heat. Rub the onion quarters with olive oil. Put them onto the grill and let them char, flipping them occasionally. Remove from grill and let cool.
For the potatoes:
Microwave the potatoes 2 minutes less than the required time. Halve the smaller potatoes and quarter the larger ones. Season with salt and pepper.
For the dressing:
Put the onions, mayo, mustard, vinegar, salt and pepper in a food processor and run until smooth.
Toss the potatoes with the onion dressing. Place into the fridge and allow to cool before serving. Best served room temperature.