Pastry cream contains wheat flour, which is not suitable for celiac patients who require a gluten-free diet. Potatoes are known as a good source of starch, minerals and vitamins. They also contain protein, dietary fibre and various phytochemicals. Their addition to pastry cream can both serve as a texturizing agent and enrich the nutritional value of the final product. This study aimed to evaluate the suitability of potatoes as a replacement for wheat flour in pastry cream. For study purposes, the physicochemical attributes of eleven potato varieties were evaluated. Among other varieties, the boiled potato variety Gala exhibited higher fibre, fat, phosphorus and potassium content; however, significantly higher protein (12.48 ± 0.08 g 100 gE−1 DW) and iron (3.12 ± 0.02 g 100 gE−1 DW) content. Higher antiradical activity (18.72 ± 0.74 mM TE 100E−1 g DW) was detected in potatoes of the variety Blue Congo. After preliminary investigation, wheat flour was replaced with mashed potatoes, making up 30% of the cream weight, and its impact on the pastry cream was studied. It was established that potatoes had a significant effect on pastry cream colour and texture. American Rose, Imanta, Rigonda and Viviana were selected as the most suitable from the eleven varieties tested. The addition of potatoes in pastry cream doubled its fibre and potassium content, whereas, other changes in nutritional value of the creams were variety dependent.