help yourself
An unlimited offering of ones goods (food, clothing, vehicle, etc) to another party, often accompanied by an encouragement (challenge) to consume as much as the receiving party is able to consume/utilise in the shortest period possible.
Housemate 1: happy Passover bro help yourself to my mums left over matzo balls they are big and delicious
Housemate 2: challenge accepted bro-mo-sexual
Housemate 2: challenge accepted bro-mo-sexual