Preheat the oven to 450 degrees F.

To make the dough: In a small bowl, combine water, honey, and yeast. Let stand until foamy, about 10 minutes. In a large mixing bowl, combine the flours, oregano, crushed red pepper and salt. Add the yeast mixture and stir until a soft dough forms.

Turn the dough out onto a floured surface and knead until smooth, adding flour as needed if dough is sticky, about 10 minutes. Clean the bowl and coat it with vegetable spray. Form the dough into a ball, put it in the bowl and cover with a kitchen towel. Let rise in a warm place until doubled in size, about 1 hour.

Meanwhile, to make the topping: Heat the olive oil and 1/4 cup wine in a large nonstick skillet over medium-high heat. Add the onion and cook until softened, adding more wine, if needed, 3 to 4 minutes. Add the spinach and cook until just wilted, about 3 minutes more. Stir in tarragon and season with salt and pepper, to taste. Set aside.

Punch the dough down and let rest for 10 minutes.

Sprinkle a large baking sheet with cornmeal. On a lightly floured surface, stretch the dough into a 12-inch circle, rolling the edge over slightly and pinching it together to form a thick rim. Place the dough on the baking sheet.

Arrange the tomato slices over the crust and top with the spinach mixture. Scatter the mushrooms and bell pepper over the top, then sprinkle with the cheese and crushed red pepper. Bake until crust is golden brown, about 35 minutes. Sprinkle with garlic salt, cut into wedges and serve immediately.