The trick: cut lengthwise down the root and make sure each piece has a bit of the side roots.

WSJ: In the Garden, Divide and Multiply: Weekend Gardener

The shape is, as you described, an egg shape, that when you cut lengthwise you see--it looks like tomato.

NPR: Getting the Taste of the Tamarillo

Ms. DE PLATT: Cut them lengthwise...

NPR: Getting the Taste of the Tamarillo

Cut the ginger lengthwise in strips and arrange it on top of the fish so the flavor can permeate the flesh.

NPR: Asian-Inspired Cooking with Tyler Florence

After halving the baguette lengthwise, cut it crosswise into quarters, to produce eight bread segments.

WSJ: Ham and Pickled Ramp Tartines | Slow Food Fast