Olive Oil (Best Option)
1:1 (use equal volume to butter)Olive oil is the traditional fat used in focaccia recipes, making it the most suitable substitute for butter. It provides monounsaturated fats that coat gluten strands, tenderizing the crumb while promoting a crisp exterior due to its lower water content compared to butter. The oil also contributes a characteristic fruity aroma and flavor that complements the bread.
To achieve the best results, use extra virgin olive oil for flavor and brush some on top before baking to enhance crust color and texture. Be mindful that olive oil is liquid at room temperature, so it will affect dough handling slightly by making it more pliable.
Compared to butter, olive oil produces a focaccia with a more open crumb and a slightly different mouthfeel, but it aligns with traditional focaccia profiles and enhances authenticity.