Wash and dry your preferred lettuce, then place in large bowl.
Chop the ham into cubes, then sprinkle in a row down the middle of the salad. Repeat with the hard-boiled eggs, strawberries, avocados, and tomatoes, so that each ingredient is in a row covering the lettuce.
In a blender, combine the sugar, vinegar, lemon juice, chopped onion, and salt until blended. With the blender running, gradually add the olive oil. Add the poppy seeds and blend.
Pour the lemon poppy seed vinaigrette in a small bowl and serve on the side.