Preparation The first thing to do is preparing the dough for the empanada. Put the flour on a worktop. Make a circle in the middle to pour a jet of oil, water, salt and yeast. Mix everything by kneading calmly until reaching a homogeneous and elastic dough with which you can work. Once the dough is ready, make a ball and let it stand for 40 minutes. The next thing to do is the garnishing for the empanada. Cut the onion in thin julienne strips and fry it in a pan. Once it is well cooked, add the chicken (previously diced in not-very-big chunks). Now is the moment to spread out the dough by dividing it into two parts: the lower part and the cover or upper part. The lower part has to be placed on an oven tray with special paper for baking. The paper can be basted a bit to avoid sticking. On this part, add the sauté of chicken and onion. Slice the tomato and the peppers thinly and add them to the garnish too. Place the upper part with the other dough part by pressing the crusts to seal it. With a cooking brush, paint the empanada with the egg. To end with, preheat the oven at 200º and after 15 minutes, put the empanada inside at 180º for 25-30 minutes. Take a careful look at the oven time since sometimes less time is needed. Presentation Take the empanada from the oven and let it cool down. Serve it on a rigid cardboard tray with a white paper tablecloth, for example.