Very Fine (Chive Oil)
Start by picking through your chives to remove any sad, wilted ones—they will ruin the flavor. To make the chives easier to handle, cut them into 1 inch pieces. You will need 1 cup of chives or 40 grams., then give the chives a hot shower for two minutes. This will help to soften the herb and more importantly help remove the grassy flavor.
Squeeze the chives to remove all of the water and the allium slime. Pro tip, I found it much easier to place all the chives in a paper towel, then squeeze out the water. It is far easier to deal with before blending than after.
In order to make blending easier, The French Laundry uses scissors instead of knives to cut the herbs into smaller pieces, which will help make the herb oil more vibrant. Chopping some herbs with a knife will oxidize the herb, causing the oil to brown.
Place half of the chives in with half of the oil. The French Laundry says to use a cup or 8 oz of canola oil, but I found that it is closer to 6 oz. Pro tip is to add enough oil to almost reach the tops of the herbs. When fully blended, the puree should have the consistency of a pureed soup.This will ensure a stronger flavored oil.
I personally like avocado oil for high heat and sunflower oil for taste which is what I use in flavored oils. Be careful not to let the blender overheat, which would dull that lovely green color.
For maximum flavor, The French Laundry stores the puree in the fridge for a day or two which will infuse the oil with more of the herb flavors. Then they strain the oil through a cheesecloth, or my preferred method is a linen like. Make sure to not squeeze the cloth which can cloud the oil. Other very fine herbs include dill, cilantro and chervil, but skip the rinsing step for them.