Issahaku left Portuguese club Sporting CP to sign a permanent contract with the Foxes after an outstanding loan stint in England.
The former English champions signed a five-year contract with the Black Stars winger, securing his stay at King Power Stadium through the summer of 2029.
The attacker, who was formerly with Steadfast and Dreams FC, was essential to Leicester City's swift return to the Premier League.
As the squad prepared for the forthcoming football season, Issahaku got back together with his colleagues at training.
Preseason friendlies for Leicester City include matches against Shrewsbury Town, Palermo of Italy, Augsburg of Germany, and RC Lens of France.
After an outstanding debut season at the King Power Stadium, the gifted young player is anticipated to play a significant role for Leicester in the forthcoming campaign.