Red onion dressing

My most-used dressing; this has a fruity component with a delicious tang that makes it the perfect companion for spinach-type salads!

1/2 red onion
1 C sugar
2 T dry mustard
1 1/2 tsp salt
1/2 C red wine vinegar
1/2 C oil

Blend all ingredients together--the spiciness of the dressing will depend on the strength of the onion, so adjust the amount of onion included accordingly (I recommend tasting the onion as you're chopping!)