A fuel injector assembly for a gas turbine engine is generally provided. The first fuel injector includes a first centerbody surrounding a first walled fuel injection circuit. A first fuel injection port is extended at least partially radially through the first centerbody in fluid communication with the first walled fuel injection circuit. The first centerbody defines a cooling circuit surrounding the first walled fuel injection circuit. The first centerbody defines a plurality of cooling openings at a downstream end of the first centerbody. The plurality of cooling openings is in fluid communication with the cooling circuit. The first centerbody defines an axially extended cooling outlet at the downstream end of the first centerbody.