Heat the oven to 350°F. Lightly oil and flour pan a mini loaf pan (6×3 inches or a pan that fits 2 cups liquid) or line with parchment paper.
In a bowl, whisk together the flour, sugar, cinnamon and salt. Use your fingertips or a fork to work the cold butter into the mix until it starts to clump up into large crumbs. Set aside.
In another bowl, whisk together the oil and sugar. Stir in the egg and vanilla. Whisk in the milk. Stir in the flour, baking powder, and a pinch of salt until just combined.
Pour half of the batter into the prepared pan and top with half of the streusel. Pour in the remaining batter and top with the remaining streusel. Bake for 40-45 minutes, or until the top is golden brown and a skewer inserted into the center comes out clean.
Let cool in the pan on a wire rack for 30 minutes, remove from the pan and let cool completely on the wire rack. Enjoy!
