pot luck
From Longman Dictionary of Contemporary Englishpot luckˌpot ˈluck British English, potluck American English /ˌpɒtˈlʌk◂ $ ˌpɑːt-/ noun 1 → take pot luck2 [countable] American English a meal in which everyone who is invited brings something to eat Can you bring a salad? It’s a potluck.potluck meal/dinner etc a potluck supper at the churchExamples from the Corpuspot luck• Before farmers had to take pot luck over whether their ewes were pregnant.