Dissolve yeast and brown sugar in water. Let sit for 10 minutes.
Stir in salt, oil and flour. Knead dough on floured surface just until not sticky. Put in greased bowl and let rise till double (1 hour)
Punch dough down, let sit on pizza pan for a few minutes. Then roll out. Let sit again for 10 minutes. Preheat oven to 425 degrees.
Roll out dough on pizza pan. Cook at 425 for about 10 minutes.
In a high powered blender, blend together spinach, mushrooms, and spaghetti sauce.
Spread sauce on the partially baked crust.
Top with cheese and other desired toppings.
Bake for 10-15 minutes or until cheese is melted and bubbly (for the best results, bake on bottom rack).