2 large stalks (8 ounces) rhubarb, cut into 6-inch pieces
2½ cups all-purpose flour
1 tablespoon baking powder
½ teaspoon kosher salt
2 cups whole milk
4 eggs
1 stick unsalted butter, melted, plus more for greasing
Poached rhubarb, for topping
Whipped cream, for topping
Maple syrup, for topping
Directions
Make the poached rhubarb: In a small saucepan over medium-high heat, bring all of the rhubarb ingredients to a simmer and cook until the rhubarb is just tender, 2 to 3 minutes. Remove from the heat and let cool completely.
Make the waffles: Heat a large cast-iron pan over medium-high heat. Add the rhubarb and cook, turning as needed, until well charred, 4 to 5 minutes. Transfer to a cutting board to cool, then finely chop.
In a large bowl, whisk together the flour, baking powder and salt to combine. Whisk in the milk, eggs and melted butter until a batter forms, then fold in the charred rhubarb.
Heat a greased waffle iron according to the manufacturer's directions. Scoop 1 cup of batter into the center of the waffle maker and cook until golden brown and crisp, 4 to 5 minutes. Repeat the process until all the waffles are cooked.
To serve, place a waffle on a plate and spoon the poached rhubarb and its liquid over top. Dollop with whipped cream and finish with maple syrup.