Poppy seed dressing

I got this recipe from my MIL. She has lots of great recipes. We had this with our spinach salad tonight.

3/4 c. sugar
1/3 c. cider vinegar
1 tsp. salt
1 c. oil
1/3 c. chopped onions
1 1/2 Tbsp. poppy seeds

Mix the first five ingredients in a blender and blend well. Pour into a 16 oz. jar with a screw-top lid, or dressing bottle (16 oz.). Add the poppy seeds and shake well.
This is yummy on any salad especially spinach salads.
Emma's notes: To add some color use a purple/red onion. It turns a fun pink color! Also we have reduced the sugar to 1/2 c or less and it is still good.