Here's a delicious summer salad.
Butter lettuce (or baby spinach)
1 red onion, sliced very thin
1/2 cup sugar
6 tablespoons white vinegar
1 teaspoon salt
1 1/2 tablespoons poppy seeds
1 teaspoon dijon mustard
Shake in dressing in jar and pour over salad. Taste as you go. You may not want all of it on the salad, it depends on how you like it. Yum!