We study the composition of a Conditional Tangency Portfolio built with the Mexican Stock Exchange Index, the Canadian Stock Exchange Index, and the US Stock Exchange Index using a Multivariate GARCH-VCC model to compute conditional volatilities and correlations for the period March 9, 2007 to March 9, 2012. As macroeconomic stability and a more mature stock market have attracted an increasing volume of foreign portfolio investments into Mexico's Stock Exchange, we document the impact of the recent Financial Crisis (2007-2009) on these flows. We compare the evolution of the Mexican market weights in the theoretically built Conditional Tangency Portfolio to the actual Foreign Portfolio Investment flows, and find that there were significant deviations which may be explained either by a "home bias" effect or by irrational behavior motivated by investors' fears.