Step 1: Preheat your oven to 350°F (175°C) and grease a 9-inch square baking pan or a similar-sized cake tin.
Step 2: In a medium bowl, whisk together the flour, baking soda, ground ginger, and salt.
Step 3: In a large mixing bowl, cream the softened butter and granulated sugar together until the mixture is light and fluffy.
Step 4: Beat in the eggs one at a time, followed by the mashed bananas, fresh grated ginger, and vanilla extract.
Step 5: Gradually add the dry ingredients to the wet mixture, alternating with the milk, starting and ending with the dry ingredients. Mix until just combined.
Step 6: Pour the batter into the prepared pan and smooth the top. Bake for 40-45 minutes, or until a toothpick inserted into the center comes out clean.
Step 7: While the cake is baking, prepare the sauce by combining the brown sugar, butter, heavy cream, and salt in a small saucepan over medium heat.
Step 8: Bring the sauce to a gentle simmer, stirring constantly, and cook for 3-5 minutes until thickened and smooth.
Step 9: Remove the cake from the oven and poke holes all over the surface using a skewer. Pour half of the warm sauce over the cake while it’s still in the pan.
Step 10: Allow the cake to cool slightly before slicing. Serve warm with the remaining brown sugar sauce drizzled on top.