Trim approximately 1" off of the bottom of the asparagus, place in a double boiler and steam in a covered pot until the asparagus turns bright green in color; approximately 2-3 minutes from when water starts to boil. Remove from pan and allow to cool slightly.
Cook ravioli according to package directions. Cooking times will vary depending on whether you are using fresh or frozen. Drain and place the ravioli back into the pot.
While the ravioli is cooking, cut the asparagus into 2" pieces.
Heat the oil in a medium saucepan over medium heat and add the garlic and asparagus. Saute for 1-2 minutes; then add the marinara sauce, half and half and red pepper. Mix well and allow to simmer 5-10 minutes (I usually let it cook until the ravioli is completely done).
Add the sauce to the ravioli and mix well. Garnish with cheese as desired.