Start by heating your oven to 350°F (175°C). Prepare a 8×4-inch cake pan by greasing it and lightly dusting with flour, or use parchment paper so the cake comes out easily.

Measure out 1 ½ cups flour, 1 ½ teaspoons baking powder, and ½ teaspoon salt. Put them together in a bowl and stir so they are evenly mixed.

Take ½ cup butter and 1 cup sugar and beat them together with an electric mixer until the mixture is light and fluffy, about 2 to 3 minutes.

Add the eggs one at a time, making sure each is incorporated before adding the next. Then add 1 teaspoon vanilla, the zest of a lemon, and the juice of the lemon. Mix until smooth.

Add the flour mixture and ¾ cup buttermilk to the butter mixture in turns, starting and ending with the flour. Stir gently until everything is combined, being careful not to over mix.

For the topping, melt ¾ cup butter and put it in a bowl. Mix in 1 ⅓ cups crushed soda crackers, ½ cup sugar, ¾ cup flour, 1 teaspoon baking powder, and ½ cup unsweetened coconut. Stir until it forms a crumbly texture.

Pour the batter into the prepared pan and smooth the top. Sprinkle the crumb topping evenly over the cake. Bake for 50 to 55 minutes, until a toothpick inserted in the center comes out clean.

Let the cake rest in the pan for about 10 minutes. Then move it to a wire rack to cool completely. Slice and enjoy this cake works well for dessert, a snack, or a sweet morning treat.