Most home bakers struggle to achieve a truly crumbly, tender texture in savory shortbread, often ending up with dense or tough crackers. The secret lies in a single teaspoon of vinegar, which disrupts gluten formation just enough to yield a delicate, melt-in-the-mouth crumb without leaving any acidic aftertaste. This dough requires a gentle hand and room-temperature ingredients to emulsify properly into a smooth, cohesive base.

Rolling it evenly ensures every cracker bakes to a uniform golden crispness, balancing the rich, buttery base with the sharp, toasted notes of nigella and sesame seeds. Handling the dough between layers of parchment avoids the need for extra dusting flour, preserving that coveted crisp, crackly finish that defines a perfect savory biscuit.