Non Belgian Belgian with low gravity
 

I just brewed a Belgian style beer with a simple recipe.

3.5lbs Extra light DME
3.5lbs Light DME
1lbs Sugar beet syrup
1.5oz Haulertau 60min
1.5oz Haulertau 30min

I am using the yeast i harvested from Ommegang.

The gravity came in a little low at 1.056 i was aiming for 1.070ish. My error was boil off rate and some extra sugar not being included.
Could i take some wort out add in some dextrose and put that back in?