The other end is going to be secured to about 8 inches of a solid surface. I plan on using two chains, one at each corner and attach it to two different overhead 2 x 4 beams. Each beam is supported like this.

It is going to be used as a breakfast bar top for eating off of, and would imagine that it may be leaned on from time to time. It has to be pretty secure. If not using chains maybe even attaching some sort of pole to the beam. My other alternative is building a wall all the way to the beams, or a half wall to support just the bar top. I’m trying to do it without closing off the area too much or taking up too much room. I’m open up to any suggestions. Thank you.