Tyrese Bout that Life -- He Drove to Vegas ... Just for Pizza ... In a $350,000 'Rolls Royce' Van

Just days before throwing down at Dr. Dre's billionaire party -- Tyrese literally drove HOURS to Vegas with his pal The Game ... inside the world's first tricked-out $350,000 "Rolls Royce" van ... just to pick up a couple slices at the Bellagio.

Tyrese tells TMZ, he picked Game up Wednesday in L.A. and made the day trip in his brand new customized ride -- what he's calling the world's first ever "Rolls Royce Ghost Sprinter" van.

The whip's stacked too -- complete with several Apple TVs, a PlayStation 4, Xbox One, Mac Mini, custom Rolls rims and grill, crazy neon "Transformers" lights, a phone charger at each seat, Internet, and even a heated floor.

Tyrese says as soon as they grubbed down at Bellagio they immediately hightailed it back to L.A. Because, why not.