Prepare the Loaf Pan:

1. Spray insides of loaf pan with baking spray or spread with melted butter. Place a half-sheet of parchment paper into the pan, leaving an extra inch or two of parchment to serve as ‘handles’,  and secure overhanging sides, if you wish. Spray the parchment.
2. Preheat oven to 325F.

Make the Streusel:

1. Place the graham crackers in a Zip-top bag. Roll over them with a rolling pin until they are fine crumbs. (Or use a spice grinder or food processor.) Place in large bowl. Add the flour, salt, cinnamon and brown sugar. Whisk or Mix well with a spoon. Add the cubes of room temperature butter. Use hands to work the butter in until it is evenly distributed and squeezing a bit with your hand results in a clump of streusel.
2. Measure 1/2 cup streusel into the bottom of prepared loaf pan, spread to cover the bottom evenly.

Make the Cake Batter:

1. In a Medium-to-Large bowl, using a hand-mixer, beat the butter, lime zest, and granulated sugar until light-colored and fluffy, about 3 minutes at Medium-High. Lower speed to Medium-Low, and add the eggs, one at a time, until incorporated.
2. In a small bowl, mix together the flour, baking powder, salt, baking soda.
3. At low speed, add the flour in three additions, alternating first with the milk, and then with the lime juice, ending with flour.
4. Spoon half the batter over the layer of streusel in the pan, spreading batter with an offset spatula or knife to edges of the pan. Then add another half-cup of the remaining streusel, followed by the rest of the batter, again spreading each layer to the edges. Using your hands, make small clumps of the remaining streusel and place atop the top of the batter. Pour remaining crumbs over so streusel is evenly distributed over the top.
5. Bake in preheated oven 42-48 minutes until a wooden skewer inserted in the middle comes out clean. 

Make and apply the Syrup:

1. Once the loaf is out of the oven, mix together the lime juice and sugar in a microwave-proof dish. Heat on high in the microwave for 45 seconds. Stir for 15 seconds to dissolve the sugar fully. Heat another 45 seconds. 
2. Stir to release some steam from the mix, then slowly pour over the loaf while it is in the pan. It might take a few minutes, but continue to pour the syrup over the entire surface of the cake, until it is all absorbed into the cake. Leave in the pan at least 10 more minutes, up to 20 mins. Using the “handles” from the parchment, carefully lift the loaf out of the pan and onto a serving plate. 

Make the Glaze:

1. In a small bowl, whisk together the confectioners sugar and lime juice. Pour over warm cake. Cool completely. Slice to serve. Wrap leftovers tightly in plastic wrap or cover with cake cover. Should keep at room temperature 3-4 days.