Heat 1 tsp. olive oil in a medium pot over medium-high heat. Add couscous, stir to coat, and toast 2-3 minutes until couscous begins to brown lightly. Add 2 cups water and vegetable base. Stir to combine, bring to a simmer, then reduce heat to medium. Cook 8-10 minutes until couscous is tender but still moist. Add additional 1-2 Tbsp. water if couscous appears to stiff. Add peas, grated Parmesan (reserving a pinch for garnish), and butter. Remove from heat, stir to combine and season to taste with salt and pepper.