The invention is a production method for an industrial convenience food product with ready-to-eat, high water activity and filler, and free of preservative, coloring agent and emulsifier, comprising the process steps of a) preparation and cooking of the bakery products, b) in order to prepare the filler (2), obtaining byproduct by executing agitation-condensation-pasteurization-homogenization processes within a single unit, reducing the temperature of the by-product and fixing the same at a certain range (50-55 °C), processing the by-product with fixed temperature in individual passages (K1,K2,K3,K4), and cooling down the same to a temperature (down to +8°C) far below the freezing point (15 °C) without allowing crystallization (constant agitation), and execution of crystallization- aeration processes by retaining air particles within the viscous matrix structure formed by minimizing the temperature variation at this temperature, c) combining the cooked bakery product (1) with the filler (2), d) packing wit
