At a first glance, Bake the Cake! looks like a chaotic game where any strategy is doomed to fall apart after the first turn. But while it's true that tactical decisions where you constantly reevaluate the situation are necessary, there are some things you can think of to turn this chaos in your favor. As so often in games, let's start at the end and understand what we want to achieve in Bake the Cake!
The first important lesson is that the objective of the game is NOT to have as many points on a cake as possible. Instead, you need to include as many other players' highest points on the cake as possible and then have more points than each and every of them. Each cake can score 23 points (5 for the cake, 3 each for the 3 layers and 1 each for the 9 ingredients) and there are three basic scenarios that may give you the victory:
You have most points on BOTH cakes.
You have most points on one cake with few scoring players while the second cake has many scoring players
Both cakes have many scoring players but the cake where you have the most points has the most even spread
The first scenario is an obvious victory. In the second scenario in a 5 player game, you could for example have 9 points and two other players 7 points each on a cake. A majority of the players will have their highest points on this cake and among them, you have the most points. The third scenario is more complex. You could for example have the points spread 7-6-4-3-3 on the first cake (with your points first) and 2-1-3-5-9 on the second cake. Three players have the highest score on the first cake and only two on the second so "your" cake wins.
It's important to bear those scenarios in mind in every tactical decision in the game. How can we then aim at those scenarios?
Scenario 1: Most points on both cakes
The first scenario is a good and safe option to aim at. If you manage to score most points on both cakes, nobody can challenge your victory. To achieve this, you should look carefully for opportunities to snatch points. One way is to put many ingredients in to play, preferrably ingredients that already have been eaten by other players. Those cannot be eaten by the players again and since they are scarce, they are likely to end up on a cake in the end.
You could also claim the majority of assistants on a part. Place the first assistant on a part whenever you have the chance. If there already is an assistant on a part, place a second assistant only if you can be sure that no other player can place a third assistant (for example, because a necessary tool is expected to be used for another part).
Finally you could place a completed part on your cake. If you want to score high, it's necessary that one of the two completed cake is yours. However, don't be too greedy! You only need 12 points on a cake - more than that is a waste of resources in scenario 1 and damaging in other scenarios, since this decreases the other players' points on the cake. This brings us to the second scenario.
Scenario 2: Most points on one cake with few scoring players
If things don't seem to go your way, i.e. another players constantly grabs more points than you, it's time to turn towards scenario 2. You now need to select one or two other players (depending on the number of players in the game) and try to get their points to their cake. Eat other players' ingredients if necessary to prevent them from being on parts that your cake needs and only pick parts with your selected players. This scenario is easier to play for if one of the completed cakes will be yours, since you control what ends up on it, but if other cakes progress faster, your last chance is scenario 3.
Scenario 3: Most points on one cake with even spread
This scenario is a difficult one. Not only must you include as many other players in a cake but you must also switch to this scenario in time, otherwise most available points will be taken already. To succeed, you really have to play a foul game. Eat ingredients and block tools to prevent high-scoring players from achieving scenario 1 or 2 and allow low-scoring players to the cakes. Check and maintain the balance constantly. Don't be tempted to restart your cake and return to an earlier scenario unless you're absolutely sure to succeed - you will need all of your actions to manage the other cakes. When the two cakes have the right spread, calculate one more time and then close the game by forcing the last cake owner to place a part. (Remember that a player is forced to take an action sooner or later when she no longer can eat any ingredients.) Scenario 3 is likely to be a close call but since you eat many ingredients in this scenario, you will also stand a good chance in a tie-break.
In conclusion, Bake the Cake! is first and foremost a tactical game but by bearing in mind the 3 scenarios of most points, most points with high-scoring players and most points with even spread, you will have a greater chance of seeing through the chaos and take the right decision.