In Italy, you’re likely to get an entire pizza to yourself. No matter how you slice it (or don’t), pizza is a social activity that is best shared with others.
For the crust, in a large bowl, mix the flour and yeast, then stir in 1 1/2 cups warm water. When the dough looks like a shaggy mess, cover the bowl with a kitchen towel or plastic wrap. Let rest at room temperature for 30 to 40 minutes.
Run one of your hands under water to help prevent sticking, then dig that hand between the dough and the bottom of the bowl, palm-side up. Firmly stretch up about a quarter of the dough and fold it over. Rotate the bowl a quarter turn. Repeat 3 times for a total of 4 turns. Cover and let rest at room temperature for 30 to 40 minutes.
In a small bowl, dissolve the sea salt in 3 tbsp. warm water. Pour over the dough. Using the same stretch-and-fold technique, gently mix the salted water into the dough until incorporated, about 8 turns. Once the salted water is incorporated, give the dough 2 more folds. Cover and let rest at room temperature for 30 to 40 minutes.
With one wet hand, gently fold the dough 1 more time, being careful not to pop the bubbles in the dough. Cover with plastic wrap and refrigerate for 12 to 36 hours. Let the dough rest at room temperature for 1 hour before making the pizza.
Preheat the oven to 450°. Brush a large rimmed baking sheet with oil. Transfer the dough to the baking sheet. Using your hands, stretch the dough evenly out to the edges of the baking sheet. In a large bowl, whisk 1/4 cup oil, 4 1/2 tsp. vinegar, and the honey. Add the radicchio; season with sea salt and pepper. Toss to coat. Arrange the radicchio evenly over the dough, leaving a 1-inch border. Bake, rotating the sheet halfway through, until the crust is puffed and golden brown at the edges, about 20 minutes.
Meanwhile, in a large bowl, toss the apple, cheese, and parsley with the remaining 4 tsp. oil and 1 1/2 tsp. vinegar. Season the apple salad.
Top the pizza with the apple salad. Drape the speck on top. Drizzle with oil. Using kitchen shears, cut the pizza into pieces.