I want to create abooking good. Attached is an image of what I created as an example. As you can see the pie slices are not the same length, as you can see I filled in the missing slice with a yellow slice.

Step 2 might not be clear. The keyboard shortcut for clockwise rotation is "]" and the default rotation step is 15 degrees, so three keystrokes rotates 45 degrees.

Thanks Paddy, looks good!

Another way, without any calculation : let's say you want to divide your circle into 17 (it will work with wathever number) equal pieces. 

• Enable snapping to guides, Nodes > Cusp Nodes and optionnaly Page Borders
• Drag from rulers two guides (with snapping to Page Borders, you can place them to match the center of page).
• Draw (hold ctrl key) a circle centered on guides intersection. Type in End field "360/17" and press enter, inkscape does the math for you.
• Open Path Effects Menu, choose Rotate copies.
• Modify Number of copies to 17.
• Press F2 to switch to node tool and drag LPE’s handle to intersection of guides.
• You're done / do path > object to path to cook LPE

If you want separate objects, you can tick Split elements option in LPE's panel before path > object to path. If you forgot to do it, you can do path > break apart for the same result. 

David - 
Another trick that doesn't use guides but you have to enable cusp node snapping. There is a snapping bug in the LPEs (  https://gitlab.com/inkscape/inkscape/-/issues/5776 ) . To work around that, duplicate the first "wedge" you created. Then you can properly align all the copies correctly to the wedge apex. Delete the wedge copy when finished.
 

Thanks, COD for this tip. Faster than using guides. It's frustrating to see the wedge apex snapping without LPE and no more snapping with a Rotate LPE

Tiling LPE is also a nightmare in terms of handles / snapping : the handles lies midway of the gap... I would love to have something more easier. 

Lol - that drove me freaking nuts one day. The control handle would snap to everything on that page I was working but not what I wanted it to snap to. That is why I filed that report. 
Maybe that trick would work on Tiling LPE as well? 

Cool stuff. Thanks all !