In large bowl, beat butter and sugar with electric mixer until light and fluffy. Add egg; mix well. Add flour and pecans; beat at low speed scraping down sides often, until mixture is crumbly. Set aside 1 cup of the mixture; press remaining into bottom of ungreased 9 x 2 in. square baking pan. Spread preserves to within 1/4 in. of edge. Sprinkle with reserved crumb mixture.