Combine the water and yeast in a large bowl. Set aside for about 5 minutes, until the yeast dissolves and the mixture is foamy.
Add the milk, flour, butter, vanilla extract, salt, hazelnut extract and sugar to the yeast mixture. Stir to blend. Cover the bowl with plastic wrap and let stand overnight at room temperature.
Heat your waffle iron according to manufacturer's instructions. Just before cooking the waffles, whisk the eggs and the baking soda into the yeast mixture.
To prepare the pecans: Oil a large baking sheet. Combine the pecans, water and sugar in a large sauté pan over medium-high heat. Stir occasionally until the sugar caramelizes, about 5 minutes. Pour the caramelized nuts onto the prepared baking sheet, spreading them evenly. Let the nuts to cool for 5 to 10 minutes.
When the waffle iron is warm, pour in about 1/2 cup of the batter. Close the lid and cook for 2 or 3 minutes. Carefully lift the lid to see if the edge of the waffle is golden brown. If it's still pale, close the lid and cook for another minute. Continue with remaining batter.
Serve with maple syrup and the caramelized pecans.Makes 8 Source: