DO-AHEAD TIP: Cook and crumble bacon.
Place spinach in a large bowl; set aside.
Heat the olive oil in a skillet over medium-high heat.
Add garlic; cook until transparent.
Reduce skillet heat to medium-low; add mushrooms and bell pepper along with turkey cubes; cook and stir until heated through (1 to 2 minutes).
Spoon hot mixture over the spinach then add crumbled bacon; toss well. Arrange salad on dinner plates.
Place dressing ingredients in a small saucepan; bring to a boil and cook until brown sugar has dissolved; drizzle hot dressing over salad.