Here is what I did (**some of the ingredient amounts may not be accurate as I was experimenting... aka 'dump & pour')
Chicken Cannelloni:
2 boneless, skinless chicken breasts, cooked & finely chopped or shredded

2 celery stalks, finely diced
1 onion, finely diced
2 cloves garlic, minced
2 Tbsp. EVOO
1 Tbsp. your favourite seasoning (I used Red Garlic Sansel by Epicure, Salt & Pepper will work as well or Italian seasoning, or a mix of dried Basil and Oregano. TOTALLY up to you. Lol)
2 cups meatless spaghetti sauce
1 small tub ricotta cheese (approx 1 cup worth)
handful fresh parsley, minced
8-10 dry cannelloni noodles
1 1/2 cups grated cheese
Cook carrots, celery, onion, garlic & seasoning with EVOO until very soft and cooked through. Meanwhile, boil water and cook noodles until just al dente. (If you over-cook your noodles they will be difficult to fill), drain and immerse in cold water to stop the cooking process. In a bowl, mix the ricotta cheese, parsley, cooked chicken, 1/2 the cooked pan veggies and a dash of chicken or veg broth if it looks too thick. Meanwhile add the spaghetti sauce to the remaining pan veggies and just warm it up, stirring occasionally. Put a bit of sauce in the bottom of a 9x13 glass dish and fill the cannelloni noodles with ricotta/chicken filling. Top with more spaghetti sauce and top that with grated cheese. Bake at 425'F for 15-20 mins. Mmmmmm I made homemade garlic/onion bread to serve with it. SO amazing.