Prepare salad dressing by combining all ingredients except poppy seeds into a blender. Blend until smooth. Stir in poppy seeds. Store in fridge.
To make candied pecans, warm a skillet over medium heat. Spray skillet with grease (like Pam) and add pecans, maple syrup, and cinnamon. Stir to coat. Continue stirring for about 5 minutes until pecans have a light golden color. Remove from heat. lay a piece of wax paper on your counter. Pour pecans onto wax paper and allow to cool and harden.
In a large bowl, add in desired amount of spinach. Top with sliced strawberries, blueberries, feta cheese, candied pecans, and salad dressing.