In July 2009, Askou linked up with English League One club Norwich City on their pre-season tour of Scotland.

He impressed suitably with his defensive displays in the club's friendly matches, also managing to score with a header against Airdrie United.

[3] He made his debut in a 4–0 win over Yeovil Town in the League Cup on 11 August, helping to keep a clean sheet.

[4] Askou became a regular starter for Norwich until picking up a metatarsal injury in a league game against Yeovil in December, which kept him out until May 2010.

[8] Askou signed a two-year contract with Danish first division team Vejle Boldklub Kolding in August 2011.

[17] After an overall defeat against AC Horsens in the Danish Superliga relegation play off games, Askou and his staff was fired on 20 May 2019.

[19] In the beginning of November 2019, it was confirmed that Askou would become the manager of HB Tórshavn in the Faroe Islands starting from 1 December 2019.

[22] In June 2023, he left AC Horsens to become the new head coach of Swedish Allsvenskan club IFK Göteborg.

[23] In June 2024, Askou left IFK Göteborg to become an assistant coach of Czech First League club AC Sparta Prague.