This puzzle is delicious because it contains a nice, juicy...
MANGO!
First solve the rebus. The words we are looking for, of 8 and 7 letters, are:
DIAGONAL ROMANIA, since there is a diagonal line comprising outlines of the country of Romania.
Now we apply the instruction at the top...
"xx?" and "(6)" are supposed to be considered together. Each 'x' means 'remove a letter', so if we remove the first two letters of the word DIAGONAL (which would be DI) we end up with AGONAL (a 6-letter word). We now need to anagram it (suggested by 'gnramaa' - an anagram of 'anagram'), and we can do this to produce the name of another country: ANGOLA.
Similarly, "x?xx" and "(4)" should be considered together. If we remove the first letter and the last two of ROMANIA (so, the R and the IA) we produce OMAN, a 4-letter country...
Finally, we apply the last instruction. If we...
'plus' the 4-letter country and 6-letter country together, in that order, we can form an overlapping string of characters: OMANGOLA.
The final "(1[5]2)" suggests we break up this final string into groups of 1, 5, and 2 letters and focus on that central 5-letter substring, which just happens to be the word MANGO - so this puzzle both involves countries and also something delicious, hence it being titled 'A delicious country puzzle'!
