While the role of Christian fasting regulations on the cuisine of the Middle Ages are relatively well known, particularly in the elaboration of meals centered around fish and vegetables as well as dairy substitutes such as almond milk, the way these regulations were altered in the Reformation era is less well known. Starting with the various dispensations for meat eating, including most notoriously that granted to Erasmus of Rotterdam, and continuing with the wholesale abandonment of calendrical fasts in the north, this paper will explore how gastronomic stereotypes differentiating between the Protestant north and Catholic south were constructed in the culinary literature. Theological tracts and dietary literature of the era will provide additional evidence for the gastronomic divisions which were not yet so clear cut or apparent in the first century of the Reformation. Yet in the end, fasting played an important part not only in liturgical distinctions, but in culinary choices and the overall cultural differences centered on food. The works of Ludovicus Nonnius in the Spanish Netherlands (Ichthyophagia) made a rational argument for maintaining fish days on the basis of health, while Reformed theologians such as Johannes Dallaeus whose works on fasting were published in Deventer, argued for a complete biblical reinterpretation of communal food regulations. Both authors reveal the ways that ideas about penitence and fasting were played out in cooking of this period.