Preheat your oven to 300°F and grease a 9×13 inch cake pan.

In a large bowl, combine all the dry ingredients.

Add eggs, milk, vegetable oil, 1/2 cup of Baileys, and vanilla extract to the dry mixture and blend thoroughly.

Gradually pour in the hot water, mixing until smooth, taking care to avoid splashes.

Transfer the batter into the prepared cake pan and bake for 40-45 minutes, or until a toothpick inserted comes out with a few crumbs.

Once baked, remove the cake and poke holes all over it using a straw or similar tool.

While the cake is warm, place the chocolate chips in a medium bowl.

In a microwave-safe measuring cup, heat the sweetened condensed milk and the remaining 1/2 cup of Baileys until boiling, then pour over the chocolate chips.

Whisk the mixture until smooth and pour it over the cake, ensuring it fills the holes.

Refrigerate the cake to let it cool and absorb the mixture.

When the cake is cool, whip the heavy cream, powdered sugar, 1/4 cup cocoa powder, 2 tbsp Baileys (optional), and 1/2 tsp vanilla extract in a large mixing bowl until stiff peaks form.

Evenly spread the whipped cream over the cake. Garnish with mini chocolate chips and a drizzle of chocolate sauce, if desired. Refrigerate until serving. Best enjoyed within 4-5 days.