Place a rack in the middle of the oven and heat to 350ºF. Use 1 tablespoon butter and 2 tablespoons flour to grease a 10-inch aluminum tube pan or two 9-by-5-inch loaf pans. Set aside.
Combine the remaining 16 ounces of butter and sugar in the bowl of a stand mixer fitted with the paddle attachment and cream for 5 minutes. Stop once to scrape down the sides of the bowl with a spatula. With the mixer running at the lowest speed, add the eggs one at a time, making sure each is fully incorporated before adding the next. Again, stopping once to scrape down the sides of the bowl. This will take approximately 3 minutes and the mixture may look curdled. Add the vanilla and salt and beat on medium speed for 30 seconds.
With the mixer on the lowest speed, add the flour in 3 installments, making sure each is fully incorporated before adding the next. After the final addition, scrape down the sides of the bowl, and then beat for 30 seconds on medium speed until almost smooth.
Scoop the batter into the prepared pan(s), dividing evenly if using two pans. Bake until the internal temperature reaches 210ºF, about 1 hour. The crust will be golden brown and spring back when pressed, but the crack around the center will appear moist.
Remove the cake from the oven to a wire rack for 10 minutes. Remove the cake from the pan(s) and cool completely on the rack. Store the cake on the rack covered with a tea towel for up to 3 days.