You'll need an NSP installer. Popular homebrew applications include:
The general installation order is: Base Game → Update → DLC. Overcooked 2 Switch NSP UPDATE DLC
You can also use these same NSP/Update/DLC files on PC emulators. You'll need an NSP installer
Overcooked 2 received massive post-launch support. Finding a comprehensive NSP bundle that includes all DLCs grants you access to an immense variety of themed kitchens, unique recipes, and wacky chefs. 1. Surf 'n' Turf Tropical beach vacation. Overcooked 2 Switch NSP UPDATE DLC