In a small saucepan, combine balsamic vinegar and honey or brown sugar. Heat over medium heat and bring to a gentle boil, stirring occasionally. Once boiling, reduce heat and simmer for 10 minutes until thickened.

In a large mixing bowl, add fresh baby spinach. Slice strawberries and add them along with blueberries, then gently toss.

Crumble feta cheese over the salad and sprinkle with toasted pecans.

Drizzle the cooled balsamic dressing over the salad, ensuring an even coat.

Divide the salad into serving bowls, garnishing with additional feta and pecans if desired. Serve chilled or at room temperature.