Preheat the oven to 300 degrees F. Line a baking sheet with parchment paper and set aside. In a big bowl, beat together the egg white and 1/4 cup brown sugar. Add the raw pecans and stir until the nuts are completely coated. Transfer the pecans onto a baking sheet in a single, even layer. Bake for 30 minutes. In a jar with a tight-fitting lid, combine the extra-virgin olive oil, white balsamic vinegar, pinch of brown sugar, sea salt, and white pepper, to taste. Cover the jar and shake vigorously for 30 seconds to emulsify. In a bowl, toss the mesclun greens, strawberries, and candied pecans with the vinaigrette.