The original mixture consists of 3 parts water and 2 parts sugar. If the chef adds one more part to each, the new amounts will be:
- Water: \(3 + 1 = 4\) parts
- Sugar: \(2 + 1 = 3\) parts
Now, the new ratio of sugar to water is:
\[ \text{Sugar : Water} = 3 : 4 \]
Therefore, the answer is 3 parts sugar to 4 parts water.