Drain oil from tuna and set aside. Put gravy in a heavy bottom saucepan on medium heat. Add nutmeg, grounded shrimp and chicken stock cube if using. Rinse the rice and add it to the gravy. Add water and salt, cover and bring to a boil.
Cover tightly and bring to boil. Immediately it starts boiling, remove lid, using a thin wooden ladle or a long fork stir from bottom to top. Cover tightly and let simmer on low heat for 10-12 minutes.
After the time has lapsed, remove lid, stir in the tuna and cover tightly. Let it simmer for 8 to10 more minutes till its cooked through.
Cut the carrots and green beans into desired sizes and finely mince garlic. Put oil in a saucepan on medium heat. Add garlic and fry till fragrant. Add green beans and carrots, a dash of salt, stir and cover tightly. No need to add water, let it steam in its own juices till desired tenderness is achieved. Serve with jollof.
You can substitute chicken stock cube with chicken stock, use enough chicken stock as you will use water to cook the jollof. Brands of rice differ, do check with the amount of water you regularly use to cook regular rice and use less than that for jollof. Remember, we using steam.