Tyler Onyango penned a new contract with Everton before joining Burton Albion on a season-long loan.
The 19-year-old midfielder has committed his future to the Toffees until the summer of 2025.
"He will bring quality to our midfield, along with steel and energy," Burton boss Jimmy Floyd Hasselbaink said.
"He's got a bright future ahead and we're happy and thankful that Everton are trusting us with their big asset."