Combine flour and beer and mix until smooth.
Line the bottom of a bowl with plastic wrap and place the Big Mac on top of it.
Pour batter over the Big Mac, press the White Castle sliders into the batter — five around the sides and one on top — and wrap the whole thing up in plastic wrap.
Wrap aluminum foil around the entire thing and place in your freezer for 2 hours or until completely frozen.
Heat oil in deep fryer or heavy skillet to 375°F.
Unwrap the White Castle Slider Breaded Big Mac and deep fry for 6 minutes or until golden brown.
Serve with Big Mac Sauce or your preferred dipping sauce.