In a small skillet, melt 2 tablespoons of butter over medium-low heat. Once melted, add 1 cup of chopped walnuts and ¼ cup of brown sugar. Stir continuously for about 3-4 minutes, or until the mixture is fragrant and the walnuts are evenly coated and beginning to darken. Remove from heat and allow the walnuts to cool on parchment paper.

While the walnuts cool, rinse 1 pint of strawberries and 1 pint of blueberries under cool water in a colander. Gently pat dry with a kitchen towel. Hull the strawberries and slice them into halves or quarters. Combine the prepared strawberries and blueberries in a large mixing bowl.

In a mason jar, combine ½ teaspoon of kosher salt, 1 tablespoon of Dijon mustard, 2 tablespoons of honey, and 2 tablespoons of red wine vinegar. Pour in ¼ cup of olive oil. Secure the lid and shake vigorously for about 30 seconds until the mixture is well emulsified and smooth. Set aside.

In a large serving bowl, place 4 cups of mixed lettuce as the base layer. Add half of the sliced strawberries, blueberries, and half of the candied walnuts. Drizzle with half of the honey Dijon vinaigrette. Toss gently to coat.

Transfer the tossed salad to a serving platter. Top with the remaining strawberries, blueberries, and candied walnuts. If desired, crumble ½ cup of goat cheese over the top, and drizzle a little extra dressing. Serve immediately.