Peanuts are legumes, along with alfalfa, clover, peas and beans. cashews are considered tree nuts, even though they are actually seeds (one seed per cashew apple). they are members of the anacardiaceae family along with mango and pistachio. 🙂 angel (who is severely allergic to all tree nuts & legumes, but not cashews!).
You can use more or less than a cup depending how high or low you want the dosage. infusion is just adding one ingredient to another. the only thing you may need to do additionally is add an emulsification agent like lechtin. you can add too much cannabutter (or pick infusion of choice.) think of a glass of water..