When mincing wet garlic, use a pinch of salt to help create friction and prevent the garlic from sticking to the knife and cutting board. For dry garlic, consider adding a tiny bit of oil to achieve a similar effect.
The moisture content of garlic significantly impacts how easily it minces. Wet garlic, often freshly harvested, tends to be slippery and can slide around, making it difficult to achieve a fine mince. The added moisture also causes the garlic to stick to the knife and cutting board. Adding a pinch of coarse salt acts as an abrasive, providing the necessary friction to break down the garlic cells and prevent sticking. The salt also draws out more moisture, further aiding the mincing process.
Conversely, dry garlic, which has been stored for a longer period, can be brittle and prone to crumbling. In this case, a tiny amount of oil, such as olive oil or vegetable oil, can help to bind the garlic together and prevent it from scattering. The oil also lubricates the knife, making it easier to achieve a consistent mince. Start with just a drop or two and add more as needed until the garlic is easier to work with.
Regardless of whether the garlic is wet or dry, using a rocking motion with a chef's knife is generally the most efficient way to mince garlic. Place the flat side of the blade on the garlic clove, hold the handle with one hand and the tip of the blade with the other, and rock the knife back and forth until the garlic is finely minced.