Having worked hard in the first period without creating too many clear chances, we fell behind two minutes after the break when half-time substitute Jack Diamond headed past Brandon Austin at the back post.
Daniel Pybus then added a second goal for the Black Cats shortly before the hour mark with the same player finishing it off from the penalty spot 10 minutes from time.
Goalkeeper Austin came in for his first Barclays Under-18 Premier League appearance since December 5 while attacker Oteh was handed his second league start of the season as we sought a return to winning ways at Sunderland's Academy of Light facility.
The first period yielded few real chances for either side and the closest we went to breaking the deadlock was when Keanan Bennetts got in behind the hosts' defence on the right side and forced a save from goalkeeper Michael Ward, with Oteh unable to make the most of the rebound as the ball broke free in the box 20 minutes in.
The home side introduced Diamond off the bench at half-time and the change paid almost immediate dividends for the men in red and white stripes as he peeled away to head home a cross at the back post following a swift counter-attack down the left.
We might have grabbed a leveller on 54 minutes when a Jack Roles free-kick from out wide found its way through to Oteh at the back post but he couldn't convert.
It was 2-0 on 58 minutes as Pybus played a one-two with Diamond to get in behind our back line before firing past Austin.
We were still struggling to create chances, although Nick Tsaroulla, on as a substitute for Oteh, went through one-on-one with Ward on the left side but the keeper saved his shot in arguably our best opportunity of the second half.
However, Sunderland completed the scoring on 80 minutes when Roles was adjudged to have fouled Elliot Embleton in the box and Pybus slotted the resulting penalty into the bottom left corner of the net.
Spurs U18s: Austin, Muscatt, Brown, Owens, Mukena, Tanganga, Bennetts (Tracey 58), Roles, Sterling, Duncan (Marsh 71), Oteh (Tsaroulla 58).