Move oven rack to lowest position. Heat oven to 450°F. Spray two 12-inch pizza pans with cooking spray. Drain pineapple; press between paper towels to absorb excess moisture.
In 10-inch skillet, cook sausage and onion over medium-high heat 5 to 7 minutes, stirring occasionally, until sausage is no longer pink; drain.
In large bowl, stir Bisquick mix, hot water and oil with fork until soft dough forms; beat vigorously 20 strokes. Divide dough in half. Pat or press half of dough in each pizza pan, using fingers dipped in Bisquick mix; pinch edge to form 1/2-inch rim.
Spread half of the pizza sauce on each pizza crust. Top each with half of the sausage and pineapple. Sprinkle each pizza with 1 1/2 cups cheese.
If you’re baking the pizzas right away, don't worry about pressing the pineapple with paper towels. For freezing and then baking the pizzas, though, this extra step helps absorb the excess liquid from the pineapple so the crust stays nice and crispy.
For a quick meal, simply take the frozen pizza out of the freezer and pop it in the oven while you toss a quick Caesar salad and cut up some fresh fruit.
For a spicier version of this pizza pie, use hot sausage rather than mild.
To Freeze and Bake: Wrap unbaked assembled pizza(s) with heavy-duty foil. Freeze up to 2 months. To bake, remove foil and bake at 450°F for 15 to 23 minutes or until crust is golden brown, cheese is melted and center is heated through.