Start by placing the raw cashews in a bowl and covering them with boiling water. Let them soak for about 20 minutes so they soften properly. This step ensures the dressing blends into a smooth, creamy consistency.
Slice the baby potatoes in half and rinse them well to remove excess starch. Place them in a pot with cold water and bring it to a gentle boil.
Once cooked, drain the potatoes and spread them out on a baking sheet or tray. Allow them to cool to room temperature before mixing them with the dressing. Cooling helps keep the potatoes firm and prevents them from becoming mushy.
Trim off the tough ends of the asparagus and cut the stalks into diagonal pieces. Steam them for about 5 minutes until bright green and slightly tender. Avoid overcooking so the asparagus stays crisp and fresh.
Drain the soaked cashews and place them in a blender with garlic, lemon juice, water, vinegar, almond butter, maple syrup, spices, salt, and pepper. Blend until the mixture becomes smooth and creamy.
Transfer the dressing to a bowl and stir in the chopped dill, chives, and lemon zest. Let it rest for about 5 minutes so the herbs release their flavors and blend into the dressing.
In a large bowl, gently combine the cooled potatoes, steamed asparagus, and diced red onions. Pour the lemon-herb dressing over the vegetables and toss gently until everything is evenly coated.
Taste the salad and adjust seasoning if needed with more lemon, salt, or pepper. This salad is best served at room temperature because the lemon and herbs become more aromatic and flavorful.