A plant-based supplement type porridge was developed with the primary goal of maximizing its protein content. The characterization of such a supplement has been made in terms of physicochemical, sensory, and textural attributes, stability, and shelf life. Seven experimental formulations were made with different levels of oatmeal, lentil and bean flour using skim milk as liquid matrix. Sweeteners, a gum, and cocoa were added to adjust its flavor and stability. Sensory, rheological, and microbiological analyses were carried out. The Weibull distribution and log-logistic were used to describe the rejection function for shelf life. There were significant differences between the porridges in color, brightness, granularity and mealy texture, sweetness, bitterness, and chocolate flavor (p < 0.05). High levels of sweeteners in the porridges were described by the pour point and viscosity, rheology and sensory. None of the porridge was on a "like slightly" scale. Sucralose at 14.4 mg/kg had the lowest liking score, as well as negative emotions. Sweetness and chocolate flavor have an impact on taste, emotional behavior, and consistency. The estimated useful shelf life was 42 and 27 days at 25 and 37°C, respectively.