Yes, ROTISSERIES is a Scrabble word!

Letter values in Scrabble US: R 1, O 1, T 1, I 1, S 1, S 1, E 1, R 1, I 1, E 1, S 1.

Is it a valid word?

ROTISSERIES is a valid word in the official Scrabble dictionary (US), the UK Scrabble Dictionary and Words with Friends (ENABLE).

an oven or broiler equipped with a rotating spit on which meat cooks as it turns
a restaurant that specializes in roasted and barbecued meats