Real gravy usually calls for your own stock and the drippings of whatever meat you're roasting. If time is short and that's not an option, you can easily whip up a batch of gravy that tastes way better than any canned or powdered versions with just a few basic ingredients.
Photo by Vicky Wasik.
For a quick and simple gravy, J. Kenji López-Alt at Serious Eats suggests you only need to look for these things in your pantry: low-sodium chicken stock, flour, and butter. And to give your gravy some savoury flavour, you'll need some soy sauce and some yeast extract like Vegemite. The recipe calls for Marmite, specifically, but Vegemite is a decent substitute for Australians. Melt the butter and add the flour to make a roux, then slowly add the chicken stock while whisking vigorously. Add some soy sauce and about a quarter teaspoon of the yeast extract, then season to taste with salt and pepper. You can even make it one week ahead of your planned meal and store it in the refrigerator. You can play around with ingredient amounts to taste, or you can use J. Kenji López-Alt's exact recipe.
The Food Lab: Why You Should Never Buy Gravy Again [Serious Eats]