Preheat oven to 375 degrees. Toss strawberries with oil and salt, then spread on a baking sheet and roast for 20 minutes.
Heat a large skillet or grilled over medium-low heat. Butter the sides of two slices of bread, place them on the skillet buttered-side down, then layer on a few slices of cheese, chocolate and strawberries. Top with a few more slices of cheese, then butter one side of the other bread slices, and place on top of the cheese. Cook for 2-3 minutes or until the cheese has started to melt, then gently flip the sandwich and cook until golden. Serve immediately!