Ismail Azzaoui opened the scoring just two minutes into the contest at Dagenham & Redbridge FC, but Sam Joel responded for Blackburn four minutes later - netting on the rebound after Sam Lavelle's effort came back off the crossbar.
Josh Onomah made it 2-1 before the break, with Azzaoui extending our lead just 20 seconds into the second half with a fine solo run and finish from a tight angle.
The young Belgian then completed his hat-trick five minutes from time.
Spurs: Glover, Walker-Peters, Muscatt, Amos, Carter-Vickers, Walkes, Georgiou (Loft, 81), Onomah (C) (Stylianides, 76), Harrison, Goddard (Ross, 88), Azzaoui. Substitutes (not used): Voss (GK), Sterling.
Blackburn Rovers: Fisher, Nyambe, Doyle (C), Pierce, Lavelle, Edgar, Mahoney, Hardcastle (Mansell, 69), Joel, Tanner, Cham (Wall, 65). Unused subs: Williams (GK), Edo, Platt.