Using late additions of your LME can help. Either turn the heat completely off, or at least way down to avoid scorcing the extract while adding to the wort. Mix the wort well while adding.
And sometimes doing a full volume boil can also help. But this assumes you have a means for cooling the additional volume (e.g. wort chiller).
Primary #1: Empty #2: Black Currant Wine
Secondary #1: Berry Rhubarb Wine #2: Empty
Kegged: Cascadian Dark Ale
Bottles: Spruced Winter Warmer, Surly Bender clone, Big 50 Barleywine, Framboise Lambic, Dark Belgian Strong, Kicked by a Moose Scotch Ale, Russian Imperial Stout, Sparkling Elderflower Wine, Barolo Wine, On Deck: Orange Pale Ale IV, Hidden Lake Nut Brown, 2H IPA III