Bring water and salt to a boil in a saucepan; slowly stir in corn meal. Reduce heat to medium-low; cook and stir until corn meal absorbs all the water, about 20 minutes. Remove from heat; stir in 2 tablespoons butter, sage, and rosemary. Add Gouda cheese; stir to incorporate.
Pour polenta into a pie plate. Refrigerate until solid and chilled, about 1 hour. Cut polenta into wedges or squares.
Heat 2 teaspoons butter in a skillet over medium heat; cook polenta pieces until crispy and warmed through, about 5 minutes per side.