After the first try, I was obsessesed with the idea of hunting down the best waffle. The second and third batch were yeast waffle recipes. Thank you Sheryl's for sharing. Begain waffle indeed superior in texture and taste. The recipe calls for overnight rest in the fridge but it sure gives you a full flavor. I was happy that the yeast gives the pleasant aroma rather than yeasty smell (imagine red wine?).
Prep time is short but you've got to plan ahead. I made two batches, one with egg added right to the batter at night, the other with egg white to be added right before cooking.
The following morning, after 7-hr rest in the fridge, the batter poofed up a bit, less than twice of last night's volumn. I could see some bubbles on surface.
Recipe adaped from Sheryl's website. I added up the sugar and cut down some butter.
Easier Belgian Waffle
2 cups flour
1-1/2 tsp instant yeast
1 stick melted butter (or less, I deducted 2 table spoon off of this)
2 cups warm milk (heated to about 110 degrees)
2 eggs
2 tsp vanilla extract
3 tbsp sugar
1/2 tsp salt
The night before: Combine and whisk together the dry ingredients in a large bowl: flour, yeast, sugar and salt. Combine the melted butter and milk. Add the mixture to the dry ingredients. Whisk eggs and vanilla together in a separate small bowl. Add the egg-vanilla mixture to the other mixture, and whisk until well-combined. Cover with plastic wrap and stick in the fridge until tomorrow morning.
The next morning: Prepare waffle iron. Stir the batter to deflate it (it should be puffy and frothy). The recipies mentioned that this batter will rise more than batters that use baking powder instead of yeast.
The below recipies is different that it added whipped eggwhite later (egg york added at night together with other wet ingredients). It makes sense to add 1/4 C more flour as I found out the batter is runny than the first batch.
1 tsp. instant yeast (Not to be confused with active dry yeast. Make sure it says "Instant")
2-1/4 cups flour
4 tbsp sugar
1/2 tsp salt
1 stick butter (8 tbsp) , melted, then cooled (or less, I deducted 2 table spoon off of this)
2 cups warm whole milk (about 110 degrees)
2 tsp. vanilla extract
2 eggs, separated
This is the batch with egg-white added last night. The dough consistency is thicker , see below photo. The other batch, I whipped egg white to soft peak, then fold into batter and it seemed the batter is a bit thinner. The problem with thin batter is that sometimes it doesn't rise up to the upper griddles and you would end up having scars on waffle surface. While , with thicker batter, the batter hold up its shape and jiggling while you pour it in. With more or sufficient amout of batter being added in the griddle, it rises and fills up to upper griddle and form nice and even brown crust. I didn't greasd , the recipe contains quite an amout of butter and it comes out from griddle easily.
After a few minutes, beside light indicator on waffle maker goes off, you can open up after all the steam disappears. Don't ever think about a sneak peak when it's not ready as half of uncooked batter will stick to the top and the other half to the botom. That way, of course , waffle structure is torn apart and won't be able to rebuilt after you turn the griddle back on. Here is the finish product. The left corner is a bit overcooked. I cannot reduce cooking time as this is to make up with the right lower corner being well-cooked.
I would say, Sheryl, you are right. Belgian waffle is the winner. Once you made this, you can never go back to baking powder waffle (if you don't mind resting batter overnighte). I recommend to put waffles in medium-heated oven, around 150 C just to keep them warm and crisp until you serve. 
