Adjust the oven rack to lower 1/3 of the oven cavity. Preheat oven to 350ºF (177ºC). Lightly spray the pizza pan with nonstick cooking spray.
In a 12-inch nonstick skillet, cook ground beef (1 pound) and onion (1/2 cup) over medium heat, until there's no longer any pink in the beef. Drain and discard excess oil.
Pour water (1/2 cup) and taco seasoning (1 packet) into the skillet and cook on medium-low until the mixture has thickened a bit and most of the water has evaporated. Cool slightly and stir in half the cheese.
Unroll crescent rolls (2 cans) and arrange them in a sun-shaped circle, with the center 4 inches wide, so that flat ends are on the inside and overlapping a bit and the tips are pointing out, on the prepared pizza pan.
Evenly spoon the taco meat mixture over the widest end of each triangle and top with the remaining cheese.
Grabbing the points of the triangles, fold them over the meat and cheese mixture, and tuck the tip under the bottom of the circle.
Place pizza pan in preheated oven and bake for 20-25 minutes, or until the crescents are golden brown.
Transfer to a serving plate and fill the center with your desired toppings.
Notes
Chill: Keep the crescent rolls in the refrigerator until ready to use. A chilled dough is easier to work with.
Filling: Make sure to cool the filling completely, or the crescent rolls will start to melt.
Bowl: I used a four-inch bowl as a guide when placing the crescent rolls on the pizza pan. This will give you a nice round inner circle which will end up beautiful when you are ready to bake. Just remove the bowl before baking the ring.
Pile it up: Pile the meat mixture high and keep it close to the center of the ring. Keep the bowl in place to keep the mixture from falling in the middle of the ring.
At Step 6, remove the bowl and gently pull the crescent roll points over the meat mixture and tuck. It doesn’t have to be perfect. When you are done, just use your fingers and make sure all the points are secure and tucked, using just a little pressure to press the points into the dough.
Egg Wash: You can use an egg wash if desired. Whisk an egg and a little milk and brush the top with the egg wash before baking. It’s not necessary, but the wash will give the crust a little gloss when baked.