The Crafting Menu in the Burger Kitchen has 5 predefined cooking slots, each capable of holding one ingredient from five categories. A Burger can be prepared when all three main ingredients occupy the slots. Each ingredient contributes a specific value to the Burger's final score.

Which Burger to prepare is determined by a random number between a lower and upper bound. The lower bound is the sum of all ingredient values, while the upper bound is calculated by multiplying the lower bound by a multiplier based on the number of ingredients used.

Burgers and ingredients are classified into five rarities:

1. Common
   
2. Uncommon
   
3. Rare
   
4. Unique
   
5. Legendary

Burgers are defined by the points ranges and ingredients have a fixed number of points for each rarity.

Let’s consider the following example. Burgers of the common rarity range from 50* to 174* and burgers of uncommon rarity range from 175* to 349*.

If we assume five common ingredients each worth 25* points, the lower bound would be 125 points. If using all five slots provides a multiplier of 2*, the upper bound would be 250 points. So the final Burger value would fall between 125 and 250 points.

This corresponds to the following chances of crafting: 40% common and 60% uncommon.
(175-125) / (250-125) = 0.4 – drop of a common Burger.
(250-175) / (250-125) = 0.6 – drop of an uncommon Burger.

*values are provided for an example. The exact point ranges for each rarity have not yet been disclosed.