1 c. safflower or canola oil
1/4 c. red wine vinegar (or to taste)
1/2 tsp. salt (or less or none)
Few (about 10 grinds) black pepper
1/4 tsp. garlic powder
2 tsp. sugar (or equivalent of artificial sweetener), or to taste
1 1/2 tbsp. catsup

Mix all the ingredients in a blender or electric mixer until foamy and well blended. Pour into a covered container and refrigerate until needed.