Pre-heat oven to 350 degrees. Coat casserole dish with non-stick spray. Prepare the zucchini rolls by slicing each medium zucchini from end to end using a wide vegetable peeler. You will need 20 slices to fill a small casserole dish.
Prepare the filling by mixing the ricotta, half of the Parmesan cheese, basil, spinach, and egg in a large bowl. Scoop the filling into a pastry bag or large plastic bag and set aside.
Pre-heat a pan on the stove. Heat the butter, garlic, and cream in a small saucepan over medium heat. Stir in the remaining Parmesan cheese until the sauce thickens. Remove the sauce from the heat.
Ladle a third of the sauce into the bottom of the casserole dish.
Cut the tip of the piping bag or plastic bag. Squeeze a strip of filling onto each of the zucchini noodle strips.
Roll each strip gently, being careful not to squeeze the filling out.
Place each zucchini roll into the casserole dish spiral side down into the sauce.
Stir the sundried tomatoes into the remaining sauce. Spoon the sauce over the rolls.
Cover with foil and bake for 25-30 minutes, until the top the sauce is brown and bubbling. Remove from oven and cool to serve.