In a blender or food processor, combine the vinegar, sugar, mayonnaise, onion, salt and dry mustard. Process until combined. Slowly stream in the vegetable oil. Stir in the poppy seeds.
Place the almonds in a small sauté pan over medium heat. Sprinkle the sugar over the almonds. Cook, stirring frequently, until the sugar starts to melt and coat the almonds. Remove from the heat and allow to cool.
In a large bowl, combine the lettuce and berries. Pour the poppy seed dressing over the top and toss to combine. Stir in the almonds and serve.
Notes
Nutrition information provided is an estimate only. Various brands and products can change the counts. Any nutritional information should be used as a general guideline.