To find out how much flour is used in the body of the dessert, we can subtract the amount of flour needed for the crumble from the total amount of flour required for the dessert.
The total amount of flour required is \( \frac{3}{4} \) cup, and the amount needed for the crumble is \( \frac{1}{4} \) cup.
Now we perform the subtraction:
\[ \frac{3}{4} - \frac{1}{4} = \frac{3 - 1}{4} = \frac{2}{4} \]
Next, we simplify \( \frac{2}{4} \):
\[ \frac{2}{4} = \frac{1}{2} \]
Thus, the amount of flour used in the body of the dessert is \( \frac{1}{2} \) cup.