Place the cashews in a bowl, cover with a few inches of water, and soak in the refrigerator for at least 8 hours or overnight. (Short on time? Cover the cashews with boiling water instead and let them soak, uncovered, for 15 to 20 minutes, then drain.)

Drain the cashews and add them to a blender along with the almond milk. Blend on high for 1 to 2 minutes, until completely smooth with no visible cashew bits (a high-speed blender will get there faster; a standard blender may need a bit longer and a scrape-down or two).

Add the Dijon mustard, lemon juice, garlic powder, onion powder, salt, and pepper. Blend again on high for 30 to 60 seconds, until fully smooth and creamy.

Taste and adjust the seasoning, adding more salt or lemon juice as needed. More lemon juice will make the dressing tangier.

Add the parsley, dill, and chives. Pulse the blender 4 to 5 times, just until the herbs are evenly distributed. Don't over-blend, or the dressing will turn a uniform green instead of showing flecks of fresh herbs.

Transfer the dressing to a covered container, such as a jar with a tight lid, and refrigerate for at least 1 hour before serving to let the flavors meld. Thin with a little extra almond milk or water for a pourable dressing, or leave as is for a thicker dip.