A rampant and pacy home side tore apart the visitors on Ranieri's return to his old side following stellar performances from Fabio Borini and Erik Lamela
Two first half goals from Juan and Fabio Borini gave Roma a commanding lead going into the break. Borini added a third early in the second half of the game before Bojan Krkic put the game beyond any doubt in the dying embers of the match.
The first half was dominated by the home side, who were simply irrepressible for the initial half hour, with the notable exception of a superb solo run from Deigo Milito that nearly created a goal out of nothing the opening exchanges.
But Roma’s immense pressure paid with just 13 minutes gone, as Juan rose high to head home Francesco Totti’s corner kick and earn the lead, following two saves from Julio Cesar to keep Erik Lamela and Fernando Gago from opening the scoring.
Inter began to get back into the match after a rough 30 minutes and nearly had a chance of their own but Yuto Nagatomo skied a cross from six yards out.
On the 41st minute mark, however, the home side doubled their lead. Miralem Pjanic added another assist to take his tally to eight for the season as he slipped Borini in towards goal. The youngster forced Walter Samuel into a slide tackle before coolly slotting the ball past Julio Cesar to send Roma into the break with a two-goal advantage.
Despite Ranieri throwing on Andrea Poli for Giampaolo Pazzini to shore up the midfield, Roma continued the second half much as they ended the first. Within five minutes, Borini added a second to his tally and a third on the night after receiving a long ball from Juan. Kept onside by Maicon, the youngster held off Lucio and slotted in past Julio Cesar.
Inter tried to press forward when possible but Luis Enrique's men continued to look the more dangerous of the two sides.
The home side added a fourth to their tally with just a minute left of regulation time to go, when substitute and debutant Giammario Piscitella found Bojan unmarked in the box. The on-loan Barcelona youngster managed to find space between three defenders to find the back of the net.
The result sees sixth-placed Roma cut the gap to Inter to a mere two points with an extra game in hand, to be played on Tuesday against Catania, while the visitors recent revival looks well and truly over.