Measure out 1 ½ cups of frozen cut green beans. Allow them to thaw before continuing. You could rinse them with warm water to soften them up quickly. Then add them to a large bowl.
Open and drain the canned beans. Rinse them off, then add them to the bowl.
Chop and measure the celery, onion, and red pepper. Add it all to the bowl and mix everything together.
Add all dressing ingredients to a separate, small bowl and mix together. You may have some difficulty mixing the tahini. If that is the case, you can microwave the dressing in 30 second increments to soften up the tahini (or use the stovetop). I find that whisking it and mashing the tahini with a fork works fine, no heating required.
When the dressing is smooth and evenly mixed, pour it onto the bean salad and mix.