irascible 

a word used to describe a person (often a coach) who, on the surface, is easily provoked to anger or very irritable but who everyone knows, deep down inside, has a heart of gold and a warm glow of support, appreciation, and kindness. The phrase is often used to describe Michael "Mickey" Goldmill, who was a fictional character created by Sylvester Stallone, portrayed by Burgess Meredith in the Rocky film series, and who, while often very irritable had a heart of gold and always wanted the best for the kids.

That coast is irascible, tough on the outside, warm on the inside.

irascible by Michael "Mickey" Goldmill March 13, 2018