Peel the orange, removing the white pith with a knife. Cut between the thin membranes to release the segments and cut the segments in half crosswise.

Heat the oil in a non reactive saucepan with a lid. Add the garlic and cook over moderately high heat, about 1 minute or until fragrant. Add the spinach and toss to coat with the oil and garlic. Cover and cook until the spinach is wilted, about 2 minutes. Remove from heat, drain off any liquid and season with salt and freshly ground pepper. Stir in the orange segments and garnish with sliced almonds.