'Using the cutting knife and the food processor jug, chop the onion, garlic and the chicken one at a time.
In a saucepan, sauté the onion and garlic in oil. Add the chicken, salt and pepper to taste and stir well. Add the cornstarch by mixing it with the milk and stir until it thickens.
Remove from heat, add the butter and let it cool. Pour all the dough ingredients in the food processor bowl and using the cutting knife, mix until smooth.
Preheat the oven to 180°C. Lay the dough on a surface sprinkled with flour and roll it out into a sheet. Then carefully add the cooled chicken mixture and carefully roll up the sheet into a Brazilian roll (rocambole).
Brush with egg yolk and bake at a medium heat for approximately 40 minutes.