Rendering pixel data from array in lwjgl

Hello people!

I’m making a 2d tilebased game that i have just ported to lwjgl. I’m now trying to implement a map & minimap into the game.

How i did it before i ported(pure java software rendering):
Each tile had an assigned rgb value which was then stored in an array and rendered out pixel by pixel(when the map or minimap was showing).

My question is:
How do i achieve an effect like this in lwjgl(+slickutil)?
I thought of rendering every single rgb value of the map as a coloured rectangle, but I imagine that would not be very effective.

Any help will be greatly appreciated!