This quickie will show you How to Draw a Cupcake using Inkscape.
Let's work on the Cupcake wrapper.
Make a Rectangle shape.
Then Add nodes to the top line segment until you have quite a few. (17 Nodes on the top segment in the picture below)
Also add a single Node to the center of the bottom line segment.
Pull the middle Node on the bottom segment downwards, and move the other 2 Nodes on the bottom segment inwards.
Then move every other Node on the top line segment down to create teeth.
Smooth bottom middle node and drag the left and right line segments inward, creating a curve.
Now we need to create Shading under each tooth we made.
Using your Pen Tool make a shape that follows the contours of the tooth with a single Node at the bottom.
Continue to do this for each tooth.
Give these new shapes a darker Shade of color than you used for the wrapper.
Smooth the tops of the teeth and the Shading underneath.
Now we'll work on the Cupcake shape.
It's a simple shape, just follow the flow of the wrapper (most of it won't be seen) and then create a muffin shaped top.
Smooth the top nodes.
Then Lower it behind the wrapper.
It's time to work on the Icing shapes.
Start with a Rectangle.
Smooth each of the nodes.
Then adjust the Handles of each node.
Do this until you get a Design you like for the icing.
Duplicate, Scale, and Stack the icing shapes.
Give each of them a different Shade of your chosen color.
Now for the Cherry on top.
Create a red Circle.
Use your Pen Tool to create a dark red colored shape for the shading, then Smooth the nodes.
Create a white Circle for the lighting.
Set a Blur for each shape.
Now for the Sprinkles.
Simply create a Rectangle and add a node at the top and bottom line segments.
Then Smooth all the nodes, and you'll have your sprinkle.
Then just Assemble your Cupcake!
Here's a shot of it without an Outline.