Bricks, Masonry, Asphalt and Concrete - i need a creative cosmetic fix

im not sure if this is the right area to pose this question but here goes....im siding a porch and to get the siding to go flush i had to cut out a section (10" by12")because the cement block was sticking out beyond the siding..nothing wrong with that except the block wasnt aligned correctly....the right side of this block (outside corner) sticks out more than the left side (gap from siding to block is 1 inch)....its just unsightly and im wondering what creative fix there could be to 'fill in' the left side.....what product can i use that will 'stick' and allow me to feather it out much the way u would with joint compound (a name brand at H. D.).....the block is sound...no crumbling and half of it has been painted...and no the cement block cannot be moved at all....also i plan on painting the block once done to match the color of siding....thx guys.
chris

This may well be what you need.

http://www.quikrete.com/diy/ResurfacingConcrete.html

Hope this helps.

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