The Foxes marked their first ever European home game at the King Power Stadium with another three points courtesy of Islam Slimani's first-half header.
Leicester were forced to withstand some late pressure from the visitors, who hit the post through Jesus Corona seven minutes from time, but the hosts held out to make it two wins from two in this season's competition.
"We suffered in the last 10 minutes but it was important to win. Concentration was high, we were resilient, I'm very happy," he told reporters.
"We played with our spirit tonight. The last pass wasn't always there, but Riyad Mahrez made one fantastic pass for Slimani."
Leicester sit top of Group G after two games, five points clear of third-place Porto.