A: Before I answer that question, why bother to increase HDL cholesterol at all? Many studies have found that people with low levels of HDL are at increased risk for heart attacks, strokes, and other complications of arteries diseased by atherosclerosis: that's why we call HDL the "good" cholesterol. Given that, you'd think that raising HDL levels would reduce a person's risk for atherosclerosis. Unfortunately, despite a lot of research, we don't yet know if that's true, nor how best to raise HDL levels.
And according to some powerful experiments by software engineer-turned-biohacker Dave Feldman, you can actually increase and decrease your cholesterol at will. It all depends on how much fat you eat — and, directly against mainstream dietary knowledge, the correlation is inverted. In other words, eating more fat will actually lower your cholesterol.