To find out how much flour is used in the body of the dessert, we start with the total amount of flour required, which is \( \frac{3}{4} \) cups.
Since \( \frac{1}{4} \) cup of flour is needed for the crumble on top of the dessert, we subtract this amount from the total flour:
\[ \text{Flour used in the body of the dessert} = \text{Total flour} - \text{Flour for the crumble} \]
Substituting in the amounts:
\[ \text{Flour used in the body} = \frac{3}{4} - \frac{1}{4} \]
Next, we perform the subtraction:
\[ \frac{3}{4} - \frac{1}{4} = \frac{3 - 1}{4} = \frac{2}{4} \]
Now, 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.