Pastrami Salmon With Fennel Slaw

Name: Pastrami Salmon With Fennel Slaw
Ingredients: 1 large fennel bulb, fronds reserved; 1 small red onion; 3 Tbsp. white wine vinegar; 5 Tbsp. extra-virgin olive oil, divided, plus more for drizzling; 4 Tbsp. Dijon mustard, divided; 1 tsp. Diamond Crystal or ½ tsp. Morton kosher salt, plus more; 1 Tbsp. plus 1½ tsp. smoked paprika; 2 tsp. light or dark brown sugar; 1 tsp. ground coriander; 1 tsp. garlic powder; 1 tsp. onion powder; 2 tsp. coarsely ground pepper, plus more; 4 4–6-oz. skinless salmon fillets, patted dry; 1 cup plain whole-milk yogurt; Torn dill (for serving)