Pre-heat oven to 350°F.
Line baking loaf pan with about ½ tbsp butter, covering all edges. Evenly sprinkle in ½ tbsp flour. Shake flour around the pan to evenly coat butter lining. Shake out excess flour from pan and discard.
Into a medium sized bowl sift together flour, salt and baking powder.
In a separate large bowl, with an electric mixer, cream together butter and sugar until light and fluffy. Scrape down the sides and up the bottom of the bowl as needed. Add lemon zest and cream again.
Add eggs to butter mixture one at a time, mix until fully combined.
In a separate glass or bowl, add buttermilk, lemon juice and rosewater.
To the butter/egg mix, alternate mixing in flour mixture, then buttermilk mixture, repeating a few times until all are combined. To keep cake light in texture, avoid over-mixing .
Pour cake batter into butter lined loaf pan. Bake for about 50 minutes. The cake is done once middle is cooked through and edges have a slight golden brown color.
Allow cake to cool for about 10 minutes. Remove cake from pan. Place on a cooling rack.