First-half goals from Nebay Haile and Corey Watson saw Middlesex lift the FA County Youth Cup at the Hive.
Middlesex, playing in their 11th County Youth Cup Final, took the lead after just eight minutes when Haile turned in Keegan Cole’s free-kick.
Cornwall, in the Final of the competition for the first time, were level instantly though when Oli Walker sent a deep cross into the box and Josh Penrose was lurking at the far post to finish.
A minute before half-time Middlesex regained the lead, Watson powering in a header.
Cornwall came close to an equaliser with two minutes to play, but Matt Buchan could only head wide as Middlesex held on.
Middlesex: 1 Lewis Todd, 2 Brandon Watts, 3 Jeremie Agholor, 4 Ryan Kukoyi (capt), 5 James Taylor, 6 Corey Watson, 7 Callum O’Reilly, 8 Malachy McGovern, 9 Harrison Livingstone, 10 Keegan Cole, 11 Nebay Haile
Substitutes: 16 Ethan Mooney for Livingstone, 12 Charlie Malin for Kukoyi, 14 Alex Hadjithemistou for McGovern
Substitutes not used: 13 Bailey Mulhall, 15 Zayn Daniels
Cornwall: 1 Luke Gwilliam, 2 Josh Otto, 3 Max Roberts, 4 Joel Allen, 5 Charlie Hambly (capt), 6 Cameron Turner, 7 Josh Penrose, 8 Ed Harrison, 9 Matt Buchan, 10 Joe Adkins, 11 Oliver Walker
Substitutes: 15 Tiago Soares for Adkins, 14 Jack Webber for Roberts, 12 Jack Rapsey for Otto
Substitutes not used: 13 Dan Stedman, 16 Alfie Flack