Preheat oven to 350° F. Line bottom of a greased 9"x 5" loaf pan with parchment paper; spray paper with non-stick spray.
In a large bowl, cream butter and sugar until combined and fluffy.
Add eggs, one at a time, beating well after each addition.
In another bowl, whisk flour, baking powder and salt; add to creamed mixture alternately with cider, beating well after each addition.
Transfer to prepared pan. Spread it out and adjust paper so the batter lays in there evenly.
Bake 40-50 minutes or until a toothpick inserted in center comes out clean.
Cool in pan 10 minutes, then remove and transfer to a wire rack. Cool completely.
For Glaze: In a small bowl, mix together powdered sugar and apple cider. Mix until smooth.
Spoon over top of cake, allowing it to flow over sides.
Video
Notes
Note: The parchment paper isn't absolutely necessary. I just think it makes it easier to pull it out of the pan when it is done and protects the edges from getting too brown if you are baking in a metal pan.