To compose a good food picture, always fill up two-thirds of your frame with your dishes/food and then manually focus on the most attractive item within the dishes, for example, the chili in the pasta attracts the attention of the eyes first, and hence the focus is on the chili. This is very important when shooting with a camera with wide aperture lens for the narrow D.O.F. but not so important for a phone camera because most likely everything will be in focus. Nevertheless, there is no harm to manually select the focus point to achieve best results. The other one-third of the picture will be reserve for any background objects or the background itself. This is to show the environment and the surroundings to create a better feel and connection to the food.
All the tips and recommendations are just for your reference only. It is your freedom and creativity to explore any style of food photography that you like. And to compile your food adventure, I would recommend you to download an app called Evernote Food which is able to compile all the information for your future reference. Or download Million Moments to compile all your pictures in a nice collage album.