In a jar or blender bottle, add the dressing ingredients. Shake to combine and set aside.
In a medium skillet, melt the butter. Add in the pecans and stir to coat. Add in the brown sugar, stir to coat. Cook for 2-5 minutes until pecans are well coated with the sugar. Line a cook sheet with parchment and pour out pecans to cool.
In a bowl, add the pineapple, spinach, cheese, and cooled pecans. Drizzle with half the dressing. Toss to coat. add more dressing as needed. Serves 6-8 as a side salad.