This latest triumph means the lads have won twice and been runners-up once in three major youth tournaments this season - winning the Eurofoot in Belgium in August, finishing second in the Dusseldorf International in March and now taking top honours in Monthey.
Tomas Pekhart opened the scoring in the final, the Portuguese side levelled but Jake Livermore struck the winner in the second half.
Coach Alex Inglethorpe reported: "We went ahead in about the 10th minute, Tomas Pekhart managed to work a yard of space in the box, controlled a cross from the right and then finish.
"They equalised just before half-time and then midway through the second half Jake Livermore scored from outside the box and that was the winner.
"We've beaten some of the best youth sides in Europe here and beaten them in a style we can all be very proud of."
After unluckily losing to Real Murcia their opening group game on Wednesday, the lads reeled off four victories in four days against FC Sion, Sevilla, Eintract Frankfurt and finally Sporting Lisbon to bring home the trophy.
Spurs: Button, Smith, Hutchins, Kasim, Martin, Butcher, Rose (Hutton, 45), Livermore, Pekhart (Olsen, 65), Mason, Townsend. Unused subs: Jansson, Mtandari, Obika, Fraser-Allen.
Our Academy squad beat Sporting Lisbon 2-1 to win the Tournoi International de Football de Monthey in Switzerland on Sunday.