- Make the flatbread dough: In a small bowl, add yeast to warm water and set aside for about 5 minutes to activate. In the bowl of a stand mixer fitted with dough hook attachment, combine activated yeast mixture with flour and salt; mix on low until elastic and smooth, about 2 to 3 minutes. Cover bowl and set aside for 30 to 40 minutes to rise.
- Make the herbed ricotta: While dough is rising, in a medium bowl, mix all ingredients until combined and season with salt and pepper. Place in refrigerator until ready to use.
- Make the fennel salad: Using a mandoline, thinly slice fennel and radishes. In a medium bowl, combine sliced vegetables with parsley, lemon zest, juice, and olive oil. Season with salt and pepper and gently toss to coat vegetables. Set aside.
- Grill dough and assemble flatbreads: Once dough has risen, turn out onto a clean, lightly floured work surface and divide into four pieces. Roll each piece to ⅛ -inch thickness. Lightly brush each side with the olive oil. Prepare a grill for medium heat and grill each flatbread until golden, about 2 minutes per side. Remove from grill and spread about 2 tablespoons of ricotta on each. Top with fennel salad, cut, and serve.