1. Toast couscous in a saucepan over medium-high heat until fragrant, about 3 minutes. Transfer to a bowl. Add 2 Tbsp. oil and shallot to pan and sauté until fragrant and softened, 1 to 2 minutes. Add broth and 1 cup water and bring to a boil. Stir in toasted couscous, cover, remove from heat and let stand for 12 minutes.
2. Transfer couscous to a large bowl; fluff with a fork. Stir in remaining 2 Tbsp. oil, lemon juice and mustard. Season with salt. Toss with spinach and pears, top with goat cheese and serve warm or at room temperature, or cover and refrigerate for up to 6 hours.