You can play Filler alone versus an automated rival chef. Gameplay is the same as a two-player game, with the following alterations.
Choose one of the six chef personality cards to play against (on the reverse of each reference card) and shuffle the matching three chef cards to form their deck. Place this chef deck face down above the recipe book.
In each turn order phase, after selecting your time card, flip the top card of the chef deck face up onto its own discard pile. This is the chef's time card. Turn order is then determined normally, comparing your time card to theirs.
When it is the chef's turn, they will normally attempt to fill a recipe. They spend no cards to do so.
The personality card details how the chef decides which recipe to fill. The filled recipe card is placed in the chef's discard pile. Ignore special ability icons when filling recipes.
If there are no cards left in the chef deck when it is the chef's turn, then they will instead perform a restock action. The chef still selects a card as normal, but instead reserves that card to the top of the deck.
Then, the chef's discard pile is shuffled to create a new chef deck.
Each personality card alters these rules in some way. If they conflict, follow the rules on the card instead.