Musar על בבא בתרא 32:13

What bothered Rashi was that Esau had been described as "the red one" already at birth (25,25). If that description was justified based on his hair or color of his skin, then why did the Torah have to tell us in 25,30 that the reason that Esau was called "the red one," was because he demanded to be given of the red dish? Besides, if a person asks for bread and he receives it, will anyone henceforth call him "bread?" There must have been something more than meets the eye in why the Torah tells us that this encounter between Jacob and Esau led to Esau being called "the red one." This is why Rashi writes that the dish consisted of red lentils, something eaten as a sign of mourning, i.e. that on that day Abraham died and was buried. Esau, the man of the field, did not mourn, but pursued his usual nefarious activities. Our sages say that he committed no fewer than five transgressions on that very day (Baba Batra 16). Since he was somewhat ashamed, he acted as if he had not been aware that the day was a day of mourning for his grandfather, and he deliberately misrepresented the dish that Jacob had prepared, calling it "this red, red stuff." Since everybody who heard Esau realised that he had shammed ignorance of the precise nature of both the dish and the reason it had been prepared on that day, he was henceforth called "the red one," as a description of his falseness. When Rav Ashi said that the Romans' own mouth "tripped them up," he referred to their statement: "the master is the swindler."