What two molecules were condensed in an aldol condensation to produce (ch3)3cch=chcoch3?

The given compound is being synthesized by condensing Acetone and Pivaldehyde (Trimethylacetaldehyde).

First Acetone is treated with Base, the base abstracts the mildly acidic proton present at alpha position to carbonyl group. The resulting specie called enolate act as a nucleophile and attacks on highly reactive aldehyde which upon dehydration yields the Aldol Product. The Reaction is as follow,