So let's get to it.
1. Here's the source image.
2. Select the bitmap source and do Paths>Trace Bitmap>Colors. I used a total of 4 scans and got this result.

3. Discard the source bitmap and ungroup the trace scan paths. Use the
to create your text objects. For this tut I had four scans, each will be filled with a different text object, thus I'll need four bits of text. I'm not very clever so I just went with the names of the colors.4. Once you've got your text objects done, fill them with your desired color. In this example I selected each scan and assigned the color to the corresponding text object. Then select one text object and do Object>Pattern>Object to Pattern. Repeat for each text object.
5. Now select each trace path and do Fill>Pattern and select the appropriate text pattern. That's it. Here's my final product

and each scan path individually to give you a better idea how it's constructed.



whoops. I did the export wrong for the red and yellows. I'm too lazy to fix it right now, but you get the idea.