Caramelized Veggies With Poppy Seed Dressing

Name: Caramelized Veggies With Poppy Seed Dressing
Ingredients: 1 small bulb fennel, plus fronds for serving; 1 bunch rainbow carrots (1¼ lb.), halved lengthwise if large; 3 small parsnips (about 7 oz. total), halved lengthwise, or quartered if large; 2 medium (about 10 oz. total) beets (preferably golden), peeled and cut into 8 wedges; 3 tablespoons olive oil, divided; 1 ¼ teaspoons kosher salt, divided; ¼ teaspoon freshly ground black pepper; 1 small clove garlic, finely grated (preferably on a Microplane); ½ teaspoon lemon zest plus 2 Tbsp. fresh juice (from 1 lemon); 2 tablespoons well-stirred tahini (sesame paste); ⅓ cup loosely packed fresh parsley leaves, finely chopped; 2 teaspoons poppy seeds