Water with a pinch of salt and a splash of olive oil (Best Option)
1/4 cup water + 1/8 tsp salt + 1/2 tsp olive oil per 1/4 cup vegetable brothWater is the primary hydrating agent in pie crust dough, and adding a pinch of salt replicates the seasoning aspect of vegetable broth. Olive oil adds a small amount of fat, which helps with tenderness and flakiness, mimicking the subtle richness broth provides.
Ensure the water is cold to prevent gluten overdevelopment, and mix gently to maintain a tender crumb. The salt and oil should be measured precisely to avoid altering the dough's consistency.
Compared to vegetable broth, this substitute results in a neutral-flavored crust that crisps well and remains flaky, making it ideal for both savory and sweet pies.