⭐ Water with a splash of apple cider vinegar (Best Gluten-Free Option)
1 cup water + 1 teaspoon apple cider vinegar per 1 cup vegetable brothVegetable broth in red velvet cake primarily provides moisture and mild acidity, which activates the baking soda and helps develop the cake's signature red color. Water alone lacks acidity, so adding apple cider vinegar replicates this effect without introducing competing flavors.
For best results, mix the vinegar into the water just before adding to the batter to preserve its acid strength. Avoid using too much vinegar as it can impart a sour taste.
This substitute preserves the cake's tender crumb and vibrant color very closely to the original, making it the most reliable replacement for vegetable broth in red velvet cake.