They include ' Permanent Upgrade slots' to keep certain upgrades forever without having to buy them again. All upgrades are permanent when bought, and carry forward through ascensions. Heavenly Chips can be spent on various upgrades during an ascension. Every Heavenly Chip you gain increases your prestige level. The easiest way to determine how many Heavenly Chips will be earned after a single reset is therefore by taking the difference of the amount of Heavenly Chips before and after the reset. Every reset, the amount of forfeited cookies is incremented by 'cookies baked (this ascension)', and will match 'cookies baked (all time)' until new cookies are baked.
The amount of Heavenly Chips is dependent on your forfeited cookies of all games.
If you ascend by pressing the 'Legacy' button, you will gain Heavenly Chips and be sent to the ascension screen. Heavenly Chips is a 'new game plus' or ' Ascension prestige' mechanic introduced in Cookie Clicker version 1.035.