In 12” standard depth camp Dutch oven over medium-high heat, brown the Italian sausage, breaking it up into crumbles as it cooks.
When the sausage is fully cooked, remove it from the Dutch oven and place it in a large bowl lined with paper towels to drain.
Pre-heat your Dutch oven for baking at 350 degrees (25 coals total = 17 top / 8 bottom).
Remove the paper towel from the sausage and stir in the ricotta, mozzarella and 1/2 of the spaghetti sauce.
Cut off a small-ish corner of a gallon-sized plastic freezer bag, spoon the mixture into the bag forcing it to the bottom of the bag and twist the unfilled part of the bag to keep the cheese mixture from oozing back out of the bag. See the quick video below that shows the steps to use a pastry bag to pipe frosting on cupcakes.
Now, pipe the cheese mixture into the uncooked manicotti pasta tubes. Alternatively, you can skip the piping and just spoon the sausage mixture into the uncooked pasta but it is MUCH more difficult.
Pour some of the remaining spaghetti sauce into the bottom of the Dutch oven, just enough to cover the bottom of the pan.
Now, place the stuffed manicotti pasta in the pan and spoon any remaining meat mixture over the top.
Pour the last remaining bit of spaghetti sauce over the top and cover to bake at 350 degrees until the shells are soft … this will take approximately 40 – 45 minutes. Turn oven and lid 1/4 turn in opposite directions every 10 - 15 minutes for even baking.