Preheat grill to 400 degrees.
Clean potatoes under cold water. Cut each potato into 1/2 inch slices
Brush both sides of the potatoes with olive oil and sprinkle with salt and pepper
Place potato slices on grill and cook on first side for 3-5 minutes, until golden.
Using tongs, once the potatoes are golden on one side, turn over and grill the slices on the other side.
Cook on second side for 2-3 minutes, being carful not to char the potatoes.
Once golden brown, take potato slices off the grill, and cool. Once cooled, cut potato slices into 1/2 inch cubes.
In the meantime, in a small bowl mix together the mayonnaise, plain yogurt, dijon mustard, onion powder. Set aside.
Pour cut potato pieces into a large bowl. Add bacon pieces and then add the dressing. Stir the salad until all of the dressing has been incorporated in the potatoes and bacon pieces.
Serve immediately. Can be refrigerated for up to 4 days.