Yes, you can reuse bhaji batter the next day, but the results may vary. The batter might thicken, and the texture of the bhajis could be slightly different.
Bhaji batter typically consists of gram flour (besan), spices, and water. When left overnight, the gram flour absorbs more liquid, causing the batter to thicken. This can lead to denser bhajis. Additionally, the flavors of the spices may intensify over time. To reuse the batter, check its consistency. If it's too thick, add a little water to bring it back to the desired consistency – it should coat the vegetables evenly without being too runny. Mix well to ensure the water is fully incorporated. Taste the batter and adjust the seasoning if needed, as the flavors might have changed. Keep in mind that the texture of the resulting bhajis might not be exactly the same as when the batter was freshly made, but they should still be perfectly edible and enjoyable.
To minimize changes in the batter's consistency and flavor, store it in an airtight container in the refrigerator. This will help slow down the absorption of liquid and prevent excessive flavor development.