What do I need to do?

This is funny because I actually had to go in the opposite direction and feed our dogs, esp. GSD more home cooked.  Anyway, I think that if you feed the cooked food mixed with the kibble and gradually decrease the cooked food you should be OK. 
 
Personally, I wouldn't eliminate home cooked.  I had to feed it more often and in greater quantity because of allergies and it has worked wonders!!  Perhaps if cooking is the problem (no time, etc.) you could give your dog things like canned fish.  I give our dogs canned salmon, mackerel, sardines packed in oil.  It's not that expensive, actually less than premium canned dog foods, and they LOVE it!  When I cook, they get pretty much what we eat; beef or chicken, turkey, lamb.  I do get them chicken and beef livers and heart and chicken gizzards; they'll get that with sweet and white potatoes or rice.  Because time is often an issue for me, I'll cook a bunch of it, portion and freeze it.  Hope this helps.

You could mix a meat and a starch (like chicken and rice or beef and potato or whatever) in a 3 parts starch to 1 part protein.  Mix it up in bulk, or do like a pound of cooked ground meat to 3 lbs potatoes, and stash it in the frige/freezer and dollup it on top of his kibble each day.  Then increase or decrease as your time allows.  I do this myself and I also use canned too.  Sometimes they only get kibble, depending, and a lot of tiems they get healthy leftovers from our meals too.
Congrats on your new furkid!

Meat and rice is a great short-term diet but over the long term isn't balaced... homecooked is great but you'd have to do research on proportions of minerals etc.
 
When you're feeding meat and rice (ground chuck is fine), boil the meat and drain off the excess fat if the dog's got a sensitive tummy. Boil the rice until it's very done and soft. Raw meat is good for dogs but I don't know about ground beef... raw-feeders may know better than me but I think you have to worry about contamination problems in raw chuck and it's better cooked.
 
It is better to switch to kibble gradually, slowly increasing the kibble and decreasing the other stuff over the course of a week. Chicken Soup is a good kibble - are you going to use their canned as well?

raw-feeders may know better than me but I think you have to worry about contamination problems in raw chuck and it's better cooked.

 
Cherokee ate raw ground beef as a large portion of her diet for several months. She did fantastically well. Dogs don't generally have problems with bacteria in food like we do.

I have 2 fu7l goldens, Buck who will be 12 on Feb. 8 and kayCee who turned 7 this past Aug. and Honey is our adopted golden mix who turned 5 last month.  They get home cooked 5 nights a week.  I put about 5 pounds of chicken thighs in a crock pot, cover with water and cook all night.  Next morning I add Chicken or calf liver (cut up) bag of green beans, cored apples (I no longer peel them), chopped sweet potatoes, and cook all day, total cooking is about 24 hours.  The bones will crumble like meal in your hands.  I give them dry kibble for brekfast, but at night they get the stew (5 nights a week) mixed with kibble.  For the day they get about 2/3 to 3/4  kibble to 1/2-1/4 cup of stew.  The other two nights they get canned (or fresh caught, baked) fish with canned, unstalted green beas 7 carrots, or unsalted mixed veggies.
 
This week their stew consisted of the chicken thighs, a pound of chicken lviers and some chicken gizzards.  I had gotten a large pack, fried some for myself, and put the rest in their stew.  I put in 2 apples and a huge sweet potato.  I was out of frozen green beans so i added half a pack of broccoli, carrot and cauliflower mix.
 
They love their stew.  Theyt also love the fresh caught fish (when I catch some)or the canned mackeral or salmon.