The neatest way to do it is to pour the 1/2 cup oil into a large glass measuring cup (2 cup size or larger), add peanut butter to the oil until the total comes out to 1 cup.
I continue adding vinegar, soy sauce& lemon juice to the measuring cup in this manner.
I pour it all out into a small mixing bowl to add the seasonings.
This way the peanut butter pours out w/the oil instead of making a mess in the measuring cup.
I use jarred garlic& ginger- this accounts for the 5 minutes prep time.
I mainly use this for tofu chunks or chicken- marinate at least one hour or overnight.
If using chicken'tenders' set aside some of the marinade (before adding the rest of it to chicken) to use as a dipping sauce.