Thirty years ago, most Americans could not tell the difference between a latte and a cappuccino. Then a little coffee shop in Seattle decided it was going to bring gourmet coffee to the masses and today Starbucks is a $22 billion company, McDonald's serves caramel mochas and 59 percent of coffee cups consumed daily in the U.S. are gourmet coffee.

Few could have predicted in the early 1980s that premium coffee would become such a bona fide phenomenon and a standard part of our everyday life. It proves the old adage "you don't know what you don't know." Nowhere is that truer than in today's booming cannabis industry.

This is what we do know. Medical marijuana is now legal in 29 states – West Virginia just joined the ranks, recreational use is legal in eight and about two thirds of Americans live in a state with some form of legal cannabis.

State legal sales reached an estimated $5.9 billion last year, and Wall Street analyst Cowen and Company predicts sales of $50 billion in the recreational market alone within a decade. This is the fastest growing industry in our economy.

I spent 20 years in asset management, most recently as chief investment officer of $115 billion of fundamental equity assets at BlackRock and was a member of its Global Operating Committee.

I live to find undervalued assets. Many cannabis assets in the private market are cheap relative to their business potential because while most acknowledge the huge growth in the industry, relatively few are willing to invest. It's a buyer's market.

Consider that state legal sales only account for about a tenth of the total cannabis consumed in the U.S., the rest is still illicit. As consumers gain greater access to government regulated marijuana products with mandated quality and safety standards, there will be very little incentive to buy pot from drug dealers. When was the last time you heard of someone buying moonshine?