Pre- heat the oven and grill the chicken for ten minutes on each side. The juices should leave the chicken. Take out from the oven and let the breasts cool then. When they do, slice them up into chunks.
Time to turn to the pecans. In a dry skillet, toast the pecans over high heat, stirring constantly for ten minutes till they start giving off their fragrance. Remove them from heat and set aside for use in later parts of the recipe.
Make the dressing now. Combine the wine vinegar, sugar, vegetable oil, onion, mustard, salt, and pepper in a blender and blend well. This will give you a smooth dressing.
Arrange lettuce on the serving platters such that they form the bed of the salad. Divide chicken chunks, strawberries and pecans among them. Drizzle with the dressing you made. Garnish with strawberry slices. The salad is all set to be served.