Strawberry Poppy Seed Salad

I love this recipe, especially now with all the strawberries in the stores. A friend of mine gave me this recipe so I'm unsure as to what cookbook it came from.  I always half the recipe for the dressing so I have included the full and half versions.

Dressing:

1/2 cup mayo

1/8 cup vinegar

1/4 cup sugar

1/4 cup milk

1 Tbsp. poppy seeds (optional)

Use with romaine lettuce, red onion, strawberries and sunflower seeds.

Dressing: (half recipe)

4 Tbsp mayo

1 Tbsp vinegar

2 Tbsp sugar

2 Tbsp milk

1/2 Tbsp poppy seeds