Yes, you can make recursive calls in FunC. And it is basically the same as in other programming languages.
Simple example of recursive pow function:

int pow (int num, int base) {
    if (base == 0) {
		    return 1;
		}
	  if (base % 2 == 1) {
        return pow(num, base - 1) * num;
		}
    int sqr = pow(num, base / 2);
    return sqr * sqr;
}