The other day I was talking to a friend who is just getting started with investing. He asked my opinion on how to build a portfolio from scratch. In this environment, that is a very tricky question. The S&P 500 currently trades at a quite rich 38x 10 year price/earnings ratio (AKA Shiller or CAPE P/E). The 12-month S&P 500 P/E is also quite high…