There are so many different styles of wall brackets out there. Here's one idea...

Here is a link that might be useful: Counter

Can you use Richelieu legs and a piece of finished formica attached to the wall ? I used an Ikea table for many many years in my kitchen. It was white, mounted on one end to the wall, curved on the other end and had one metal leg. I was amazed at how long it held up, how functional it was and the weight it held. A inexpensive peninsula, it served as a breakfast and dining table and buffet table for parties.

I actually had thought about butcher block... I would rather not have legs, but looking at that pic helps..The brackets look great! Does anyone have input about how deep the counter should be to comfortably have a meal there?

7' might be a tad crowded for 4 stools unless you can sneak one in on the end....i usually figure 24" per person. If you plan on using the end, then you should have the counter 24" deep. If that's too deep, then you might want to at least round the ends as that gives a little more elbow room to whoever is sitting there.

"Table-height surfaces should be at least 18 inches deep, because your knees are bent at right angle. Taller chairs require less bend in the knees. The NKBA recommends a depth of 15 inches for a counter-height surface and 12 inches for a bar-height surface. "

Thank you for the measurement guidelines...big help

I've used brackets from Rakks several times. Mostly the ones that are hidden in the wall but they have many and support substantial weight and depth.
My office has an "L" section of desk 6 plus ft on each, 23 in deep- 1-1/2" tick wood top. There is a 15" cabinet on each end- the rest is on two suppots. Did a clients office with an 8 by 10 ft ell with just brackets.

Here is a link that might be useful: rakks supports