Can dashes stack

So I’ve been playing rouge and I’m wondering, can I stack mt bonus action dash with an action dash giving me 120 feet of movement 

If you use Dash multiple times, you get its benefit multiple times. If your speed is 40 feet, then Dashing twice will let you move 120 feet.

Yup, with the proper use of skills and abilities I've had players move obscene distances in a turn, just pray your DM doesn't decide to pull a Mel Brooks on you and have a horde of baddies around the corner when your movement ends!

Human Monk 10/fighter 2, move, dash, step of the wind, action surge, dash = 200 ft of movement

Just need to double check something with the OP as 120 ft movement number is raising flags in my brain.

Dash grants you extra movement (equal to your speed) in your turn that's in ADDITION to normal movement in a round. 30 ft movement normally, + Dash action (another 30 ft), and + Dash from cunning action = 90 ft in a turn.

Dash does not double speed in case that's what jimmop is thinking: 30 ft speed x doubled with Dash action for 60 ft, and doing it again with cunning action for another 60 ft for 120 ft in a turn. 

As InquisitiveCoder has said, if your speed was 40 ft, then you could 40 ft move, 40 ft Dash, 40 ft cunning action Dash for 120 ft in a turn.

I figured out how to get 480ft

Monk 2/Sorcerer 5 Tabaxi

30ft + (unarmored movement +10) + longstrider (+10) + mobile (+10) = 60ft

60ft x 2(dash) x 2(Feline agility) x 2(Haste) = 480ft

he can also walk on water and walls.