Finely grate 1 Tbsp peel from orange; set aside. Cut top and bottom from orange so it sits flat. Working from top to bottom, cut off peel and pith. Hold orange over blender and carefully cut out pieces between membranes into blender. Squeeze in any remaining juice.
Add shallot, vinegar, maple syrup, mustard, and salt. Blend until pureed. With blender still running, slowly drizzle in oil. Stir in reserved orange peel and poppy seeds and transfer dressing to cruet or small bottle.
Recipe Notes
Per 1 Tbsp serving: 53 calories; 0 g protein; 5 g total fat (1 g sat. fat); 3 g total carbohydrates (2 g sugars, 0 g fiber); 85 mg sodium