Fresh strawberries and baby spinach are a match made in heaven. The herbal flavor of the spinach is tempered by the berries' sweetness; when you add some tangy goat cheese, a handful of fresh mint, and a fruity strawberry vinaigrette, the result is memorable.
Nutrition note: Red + green = better iron absorption! When you eat iron-rich spinach together with other foods rich in vitamin C (like strawberries), the combination helps your body absorb the iron more effectively.
Place the strawberries and sugar in a food processor or blender and pulse until the berries are chopped very fine. Add the vinegar and let the mixture rest at room temperature for 1 to 2 hours. Transfer the mixture to a fine mesh sieve set over a clean bowl and press gently to drain. Discard the solids and reserve the strawberry vinegar. You can keep the vinegar refrigerated, covered, for up to 2 weeks.
Place 2 tablespoons of the strawberry vinegar in a glass jar. Add 3 tablespoons of olive oil, the salt, and freshly ground black pepper to taste. Close the lid tightly on the jar and shake vigorously to combine. Let the vinaigrette rest at room temperature while you assemble the salad.
Place the spinach, mint, and strawberries in a large bowl and toss to combine. Add half of the strawberry vinaigrette and toss again, adding more dressing as desired. Sprinkle the salad with the crumbled cheese and serve immediately.