Romelu Lukaku and Lautaro Martinez put on a masterclass of clinical counter-attacking football, as Inter got past Sassuolo for a 10th consecutive victory.
This game was rescheduled from last month due to a COVID outbreak in the Nerazzurri camp.
Lukaku scored his first Serie A header since July 2020, meeting the Ashley Young cross from the left.
Lautaro Martinez struck on the counter moments after Sassuolo penalty appeals for a Stefan de Vrij shirt tug on Giacomo Raspadori.
The visitors finally got something for their 70 per cent possession, Junior Hamed Traore making the most of an Achraf Hakimi error for a consolation goal.