Heat either a grill pan or large frying pan to medium heat.
In a medium saucepan, bring the water and 1 teaspoon salt to a boil. Stir in the couscous, cover and immediately reduce heat to low. Simmer for 2 minutes, then remove from heat. Keep pan covered and allow couscous to steam for 8-10 minutes. Remove lid, fluff couscous with a fork and add half of the spinach.
Cover pan again and allow spinach to steam for 2 minutes until slightly wilted. Stir spinach into couscous to incorporate, then add remaining spinach and cover again for another 2 minutes. Combine spinach and couscous, drizzle with 1 tsp. olive oil and season to taste with salt and pepper. Return lid to pan and keep covered while sausages cook.
If using a grill pan, brush with oil once hot. Place sausages on grill and cook until lightly charred on one side, about five minutes. Flip sausages and continue cooking until lightly charred and heated through, about another five minutes.
For a frying pan, add oil once pan is hot. When oil shimmers, add sausages, turning until browned on all sides and warmed through. Total cooking time should be 7-9 minutes.