This study evaluated the role of plant-based biphasic gel (bigel) formulations in replacing commercial fats (i.e., butter and shortening) in shortbread. Bigels were prepared by combining an alginate/κ-carrageenan-based hydrogel (20% w/w) with a rice bran wax/soybean oil oleogel (80% w/w), with and without emulsifiers (monoglycerides). The formulated bigels successfully mimicked solid fat functionality in short doughs by providing the desired shortening power and producing doughs of low elasticity. The resulting cookies were more tender and presented comparable cellular structure, moisture content, and water activity than traditional shortbread. Bigel cookies spread at a lesser degree than butter and shortening cookies, which was attributed to the bigels’ high melting range and potentially representing an advantage in products where lateral expansion is undesired (e.g., cookies of specific shapes). The presence of monoglycerides in one of the bigel formulations did not provide additional quality improvements to the cookies. Therefore, the bigel formulation without monoglycerides can be considered not only a plant-based but also a clean-label alternative to solid fats. Bigel performance was also compared to that of a commercial low-saturated fat palm oil-containing spread. Unlike bigels, this vegetable oil spread failed to produce short doughs and shortbread of acceptable quality. Overall, the bigels represent a suitable alternative to commercial solid fats with an improved fatty acid profile, free from palm oil and animal-based ingredients.